First of all, I must say that this guide makes some assumptions that you have finished most of the normal puzzles in the game and are well familiar with all of the mechanics.

It is kind of pointless to look at a guide for secret extras when you haven't completed the non secret part yet.

If you need help with the normal puzzles or understanding basic mechanics, do check out this guide instead, It does a great job of explaining everything!
http://cs2bus.com/sharedfiles/filedetails/?id=354777976

If you still are in need of help after checking this guide, you should consider checking a more descriptive video guide or something. I can't help everyone, sorry...

That being said, let's move on to other things!

Update: If you're looking for the Road To Gehenna Stars, check this out:
http://cs2bus.com/sharedfiles/filedetails/?id=486737481


Each section covers a single level. In each section has two parts:

• How to find the star
  
• How to actually get the star

For each part I tried to list hints, starting from vague directions and leading to the actual solution. So if the first hint doesn't help, you can check the next one, and so on.

The Stars are secret items that can then be used to unlock Secret Levels where you can complete more Secret Puzzles! The gates to these Secret Levels can be found in each of the three World Hubs.

There are a total of 30 stars. 10 Stars are needed to open a Secret Star Gate.

Well... Technically you can get more Stars by using the Sigils of Elohim codes. So even if you can't find all of the Stars on your own, you could still get enough without resorting to a guide like this!

Good luck finding the Stars, hopefully you won't have to use this guide too much.

If I've missed anything, please let me know in the comments! Also, it helps to specify if you want more hints for a Star or just a more detailed solution.

Where is it?

• 1st hint: After arriving in the courtyard with the first puzzle gate, somewhere to the right...
  
• 2nd hint: It's not within any of the other puzzle areas.
  
• 3rd hint: The entrance is near the "Only the Two of Us" puzzle
  
• 4th hint: A switch will open the gate...
  
• Solution: The gate to the right of "Only the Two of Us" - open it with a switch located in the corner to the right of the gate, behind a wall.

How to get it?

• 1st hint: You need to get a jamming device from somewhere else - that much is obvious...
  
• 2nd hint: It's not from any other puzzle area that has a Tetromino...
  
• Solution: Go back to the "tutorial" puzzle with the Mine and the Turret. To get past the Turret, on your way back, just before entering the corridor where the Turret would shoot you, turn left and look for a ladder on the wall in front of you. Then get both Jammers past the Mine - Jam the mine with the first Jammer, then double jam it with the second - next pick up the first Jammer an use it to jam the Turret instead. The second Jammer shoudl be free to take to the Star now.

Where is it?

• 1st hint: Outside the puzzle areas...
  
• 2nd hint: No further from the spawn than the puzzle entrances.
  
• Solution: From the spawn, turn right. Afterwards, go straight ahead and look behind the wall. (Or, from the entrance to "Hall of Windows", just follow the outer left wall.)

How to get it?

• 1st hint: There is a Jammer you can use in a hidden place outside the puzzle areas.
  
• 2nd hint: It's behind a locked gate.
  
• 3rd hint: The gate is right behind the Spawn, but you'll need keys.
  
• 4th hint: The keys are within one of the puzzles.
  
• 5th hint: It's in the puzzle area of "The Guards Must Be Crazy"
  
• Solution: In "The Guards Must Be Crazy", after solving the puzzle and getting the Sigil (Tetromino) - From the entrance, go forward until you must turn left. After turning left and going through the corridor, there should be an opening on the left wall, look around in there for some keys, then go open the gate behind Spawn to get the Jammer you need to open up the way to the Star

Where is it?

• 1st hint: You can't really see it until you get it - I mean, it's not visible.
  
• Solution: Near the spawn, under the ground, see how to get it for actual useful hints.

How to get it?

• 1st hint: Those 24 columns with buttons seem interesting don't they?
  
• 2nd hint: That QR code that doesn't seem to translate is also intriguing, is it not?
  
• 3rd hint: Translate the QR code yourself! Don't have a Smartphone? Take a screenshot, process it a bit, and use Google to find a QR decoding website - that's what I did. Or if you can't be bothered with all that, just read the next hint.
  
• 4th hint: The decoded message is: "THE EAGLE HAS LANDED 31 39 36 39 2f 30 37 2f 32 30 20 32 30 3a 31 38 Now is the time of tranquillity, and I shall rest and observe the Earth.
  -- Uriel4"
  
• 5th hint: Convert those hexadecimal numbers to Ascii!
  
• 6th hint: The numbers mean: 1969/07/20 20:18 - try using this date in combination with those columns with buttons. Fun fact: The phrase "The Eagle Has Landed" was used by Neil Armstrong, one of the three astronauts that took part in the first Moon landing (the other two being Michael Collins and Edwin "Buzz" Aldrin). "Eagle" was the name of the lunar lander space vehicle they used. The landing took place on 20th of July 1969 and the landing site was at the "Sea of Tranquility".
  
• Solution: Press the buttons on the columns marked VII (7) and XX (20)

Where is it?

• 1st hint: I really don't have any hint here... Should be impossible to miss.
  
• Solution: In "A bit Tied Up", after passing all the Turrets just keep your eyes open.

How to get it?

• 1st hint: Just like "Only the Two of Us" in Level A1...
  
• Solution: Just get all three Jammers behind the first Barrier and open the Barrier to the Star. If you got this far you shouldn't even need this solution.

Where is it?

• 1st hint: In one of the puzzles...
  
• Solution: Look around in "Push it Further" - Opposite to the blue laser source.

How to get it?

• 1st hint: The laser source you need is not in this puzzle area. Think outside the box.
  
• 2nd hint: You need to get a red laser from one of the other puzzles, only question is, how?
  
• 3rd hint: Sometimes the answer lies above...
  
• 4th hint: Look for a connector on top of a stone column near "Push it Further".
  
• Solution: From the "Push it Further" entrance, follow the road across the intersection with the main road. To your left you should see a column with a connector on top of it. Back in "Push it Further", use a Laser Connector to link the Red Receiver to the Column-Connector. Afterwards go to "Above all That" and use one of the Laser Connectors here to connect a Red Laser Source to the Column-Connector. You can now go back to "Push it Further" and grab the Star.

Where is it?

• 1st hint: If you've completed all puzzles in this levels you should've seen it by now..
  
• 2nd hint: In "Things to Do With Two Boxes"...
  
• Solution: From where you pick up the Sigil (Tetromino), go forward up the stairs and direct your eyes beyond the metal fence.

How to get it?

• 1st hint: You can't jump over the walls.
  
• 2nd hint: Maybe you can open a secret wall somewhere?
  
• 3rd hint: After solving the puzzle, go up the stairs and you'll see the Star through the metal fence. If you look to the wall opposite to the blue forcefield, to the right, you can see a yellow cable. It's kind of hard to spot. (It can also be seen from the ladder that leads back to the start of the area, in third person.) Follow the cable!
  
• 4th hint: The cable seems to go under the entrance to the puzzle area... Look around some more?
  
• 5th hint: After entering, immediately turn left and look in the corner on the side with the entrance brick arch structure. You should find a switch there.
  
• 6th hint: Great, now there's a Red Laser receiver to deal with. I guess just look around for a Laser Connector?
  
• 7th hint: Get a Red laser beam into the puzzle area from somewhere else.
  
• Solution: After entering, immediately turn left and look in the corner on the side with the entrance brick arch structure. You should find a switch there. Look around the newly opened area for a Laser Connector (follow the corridor on the right side of this area). Use it to connect with a Red Laser from "One Little Buzzer"

Where is it?

• 1st hint: It's hidden in one of the puzzles.
  
• 2nd hint: It's in a place you wouldn't normaly think to go to.
  
• 3rd hint: "Friendly Crossfire"...
  
• Solution: In "Friendly Crossfire" go through the right-side Barrier after opening it.

How to get it?

• 1st hint: Should be kind of obvious.
  
• Solution: Just kind of, walk towards it, then through it.

Where is it?

• 1st hint: It's not in any of the puzzles...
  
• 2nd hint: It's hidden beyond sight, but jumping around in third person might reveal it...
  
• Solution: Between "Mobile Minefield" and "Deception" gaze over the wall.

How to get it?

• 1st hint: You need something to boost you over the wall.
  
• 2nd hint: Something like a Hexahedron! (The cube thing, or box thing.)
  
• 3rd hint: Well you can't get it from the puzzle areas... Look around some more!
  
• Solution: Get the Hexahedron from the far right corner - the side with "Bicromatic Entanglement" before entering the puzzle, turn left and look around behind some ruined walls. Use the Hexahedron to jump over the wall to the Star.

Where is it?

• 1st hint: Look around for anything suspicious in one of the puzzles...
  
• 2nd hint: Maybe some element that you've never used in solving the puzzle?
  
• 3rd hint: Something like a Blue Laser Receiver.
  
• Solution: Beyond the Blue Laser Receiver Barrier in "Two Pesky Little Buzzers"

How to get it?

• 1st hint: Kind of like that one Star in Level 5...
  
• 2nd hint: ...by which I mean get a Blue Laser in from another puzzle!
  
• 3rd hint: The other puzzle is "Locked From Inside". It's the only one that aligns with the "Two Pesky Little Buzzers" gate.
  
• Solution: Solve "Two Pesky Little Buzzers" then get a Blue Laser beam through where the metal gate just lowered.

Where is it?

• 1st hint: Should be hard to miss...
  
• Solution: In the puzzle "Something About a Star"

How to get it?

• 1st hint: Like with some previous Stars, you've gotta 'think outside the box'.
  
• 2nd hint: ...Get a Red Laser in from another puzzle!
  
• Solution: Use the Red Laser Source from "Window Through a Door".

Where is it?

• 1st hint: Hidden away out of sight...
  
• 2nd hint: ...in one of the puzzles.
  
• 3rd hint: Check out "The Tomb".
  
• Solution: Immediately after entering "The Tomb", turn right and look behind the statue - you will see a Barrier blocking your way.

How to get it?

• 1st hint: The tools you need to open the Barrier are nearby.
  
• 2nd hint: Get the Jammer from the first puzzle room in "The Tomb".
  
• 3rd hint: To deactivate the second Barrier, you'll need to look to another puzzle for a Laser Source.
  
• 4th hint: Look to the Moon for help.
  
• 5th hint: Use the Laser Source from "Moonshoot".
  
• Solution: Get the Jammer from the first puzzle room in "The Tomb" to open the first Barrier. However, before opening the Barrier, use the Jammer to get the two Laser Connectors to entrance of "The Tomb". To open the second Barrier, solve the "Moonshot" puzzle, then use the floating Laser Connector in combination with the two Connectors in "The Tomb". Note: You mustn't take the two Connectors down from the secret Corridor, just place one at one end of the corridor, and one at the entrance of the corridor.

Where is it?

• 1st hint: Hidden away out of sight...
  
• 2nd hint: ...in one of the puzzles.
  
• 3rd hint: Look for a certain Laser Receiver in one of the puzzles.
  
• Solution: In "Blown Away", just after entering, to the left of the entrance there's a Red Laser Receiver, activating it will open the way.

How to get it? (My solution)

• 1st hint: Like with previous Stars, you've got to think outside the box again!
  
• 2nd hint: Similar to the Star in Level B2, you'll need an elevated platform with a Laser Connector on it.
  
• 3rd hint: The Red Laser Connector you need is in "Whoosh!" but it is too low, maybe there's a way to raise it?
  
• 4th hint: Beyond one of the walls there's a Button that will raise the Connector. You'll need a Hexahedron to press it down.
  
• 5th hint: You'll need a Fan and two Hexahedrons to boost over the wall...
  
• Solution: In the puzzle "Whoosh!", you'll have to raise the Red Laser Connector. To do this, you'll need to get a Fan and two Hexahedrons. Place the Fan on the bottom Fan Socket next to the Blue Laser Source. Then place the two Hexahedrons stacked on top of eachother, between the short wall and the Fan - about halfway between them should work, but try placing them somewhat closer to the wall. Now jump into the Fan's wind, then jump onto the stacked Hexahedrons. From here you can jump ON the wall itself and pick up one of the Hexahedrons. Take it with you beyond the wall and go around until you find a Button. Place the Hexahedron on the Button - this will raise the Red Laser Connector. Now go back into "Blown Away" and use the Laser Connector here to connect the Red Laser Receiver to the floating Connector from "Whoosh!".

How to get it? - Alternate Solution
Credit goes to FreeMetal who first informed me about this. FIGBird also provided details about this solution.

• 1st hint: You have all the tools you need in this puzzle...
  
• 2nd hint: ...but you'll need to gaze into another puzzle for the Red Laser.
  
• 3rd hint: Try stacking the Hexahedron and Laser Connector in a creative way
  
• Solution: From the front of the barrier, look to its upper right corner to see the fixed Laser Connector from "Woosh!". Back up as much as you can. Place the Hexahaedron, grab the Laser Connector and link it to the Red Laser Receiver and the Laser Connector from "Woosh!", then place it on top of the Hexahedron - the Red Laser Beam should go through the barrier (You might need to jump on the Hexahedron to be able to link to the Connector from "Woosh!"). Last thing you need to do is step on the button to disable the barrier. Stay on it until the secret door to the Star opens up.

Where is it?

• 1st hint: Hidden in one of the puzzles...
  
• 2nd hint: In one of the puzzles near the Sphinx.
  
• 3rd hint: ...You can see some Fan Wind effect beyond a wall where the Star is.
  
• Solution: In "The Right Angle", next to the first Floating Shocker there's a wall beyond which a Fan's wind effect can be seen.

How to get it

• 1st hint: You'll need some help to boost over the wall.
  
• 2nd hint: Sometimes your enemies can be your friends.
  
• 3rd hint: You can stack Hexahedrons onto the Shocker Spheres.
  
• 4th hint: There are two Hexahedrons in "The Right Angle" puzzle.
  
• Solution: Use the first Hexahedron to trap the Shocker Sphere at it's patrol limit where it's closest to the wall (the side with the tree). Get back to where you picked up the Sigil (Tetromino) and look for the second Hexahedron. Place it on top of the Shocker, jump onto the first Hexahedron, then from there jump upon the second one (the one you just placed on the Shocker). You should be able to jump over the wall from here.

How to get it - Kitusss' Solution

• Solution: The enclosed area where the star is located is next to a small wall and a statue. By using a cube, you can jump on the statue's legs and proceed to jump on the wall and in the star area! Author's note: I find the jump to be too tricky for me...

Where is it?

• 1st hint: Hidden beyond sight outside of the puzzle areas...
  
• 2nd hint: Look for Uriel4's QR message.
  
• 3rd hint: Look between the Sphinx's front paws.
  
• Solution: The Star is hidden within the Sphinx itself! But how do you unlock it?

How to get it? - The 'normal way'
Credit goes to p277 for poting out something that I was missing.

• 1st hint: In Uriel4's message, "The Burning Heart" refers to the Sphinx's heart, while "The Highest Peak" is the literal highest peak in the area. (The top of the Pyramid)
  
• 2nd hint: Try looking at "The Highest Peak" with a Laser Connector in your hands - notice anything?
  
• 3rd hint: There's a hidden Blue Laser Source at the top of the Pyramid and a hidden Blue Laser Receiver in the Sphinx's chest.
  
• 4th hint: You'll need to get a laser connector to the Sphinx...
  
• Solution: When getting the other Star in the level, grab a Laser Connector and take it out of "The Right Angle" puzzle area using the fan. Your next step is to simply aim the Connector at the top of the Pyramid - there should be a Blue Laser Source that you can select. Afterwards aim it at the chest of the Sphinx - there should be a Blue Laser Receiver there for you to select. Link the two and it will open a secret room in the front of the Sphinx, between its paws.

How to get it? - My first solution, aka the hard way
Seriously, this is just a more complicated way to solve it.

• Solution: When getting the other Star in the level, get the two Laser Connectors out of "The Right Angle" puzzle area. (Jump over the wall with them in hand, then get them out one by one with the Fan). Use the two Laser Connectors to connect the hidden Receiver in the Sphinx's Chest (just above Uriel4's message) to the Source in "A Box Up High".

How to get it? - My alternate solution

• Alternate Solution: In "Wrap Around the Corner" place the Laser Connector next to the platform with the Sigil (Tetromino). From the platform you can pick it up, then sprint and jump over the right side wall (facing to the back of the puzzle area). Go back to the Spawn area corridor with the Laser Conector. Aim the Connector at the Blue Laser Receiver hidden in the Sphinx's chest (just above Uriel4's message). Then aim it at the Blue Laser Source in "Wrap Around the Corner". Place the Connector near entrance "Wrap Around the Corner" - it should be in the middle of the main corridor. It's tricky to align it with the gate and Source in "Wrap Around the Corner" but it can be done.

Where is it?

• 1st hint: The Obelisk...
  
• Solution: It's on top of the Obelisk!

How to get it?

Obviously, you need to activat ethe gadgets at the bottom of the Obelisk, so I'll split the hints and solutions based on what you're activating:

Actiavting the Fan

• 1st hint: The Fan is hidden away near one of the other puzzles. It's a secret extra Fan.
  
• 2nd hint: The Fan is "Behind the Iron Curtain" or more accurately, next to it.
  
• 3rd hint (Fan): The Fan is behind a wall next to the Sigil (Tetromino) in "Behind the Iron Curtain".
  
• Solution: The secret extra Fan is behind a wall next to the Sigil (Tetromino) in "Behind the Iron Curtain". Proceed with solving the puzzle as normal, but don't drop the two Hexahedrons down after getting them up using the Fan. Instead, place one in the Fan's wind, and place the other near the edge of the elevated platform. Jump on to the Hexahedrons, from the floating Hexahedron you should be able to jump onto the wall and down to where the secret Fan is located.

Actiavting the Fan - twix5.65's Solution

• 1st hint: You can get a Fan out of "Alley of the Pressure Plates
  
• Solution: In "Alley of the Pressure plates, you can use float yourself over the wall using the Recording Mechanic, a recorded Fan and a Hexahedron.
  First, replaace the Connector on the button with the Hexahedron. Next, start a recording, wait around for 15 seconds then activate the Fan's Blue Laser Receiver with the Connector. Wait around a bit then end the recording.
  Now, take the real Fan out of the socket, and place the real Hexahedron on top of the ghostly recorded Fan. It won't auto-stick, but if you center it right it will work normally. Grab the Fan, jump onto the Hexahedron, and once your recording activates the Fan you can climb onto the walls and out of the puzzle area with the Fan.

Actiavting the Fan - plasticzaku's Solution

• 1st hint: You can get a Fan out of "Four Chambers of Flying"
  
• Solution: Get the cube and place it on one fo the fan assemblies. Grab a Fan, jump on top of the cube, jump onto the wall and exit the puzzle area.

Activating the Laser Receiver - My solution

• 1st hint: The Blue Laser beam should come from the side where the Receiver is facing.
  
• 2nd hint: The Blue Laser beam should come from "Slightly Elevated Sigil".
  
• 3rd hint: The Laser Beam should go over the walls in "Slightly Elevated Sigil".
  
• Solution: Go in the "Slightly Elevated Sigil" puzzle. You'll need the two Laser Connectors and the Hexahedron. Place the Hexahedron onto the Fan. Then place a Laser Connector next to it. The next part will have to be executed quickly: Use the second Connector to activate the Fan, and immediately grab the other Connector and jump onto the Hexahedron. You should end up floating up high with a Connector in your hand. Simply jump to the walls and walk to a spot where you can connect the Obelisk Receiver to the Blue Laser Source here.

Activating the Laser Receiver - AnttiM's solution

• 1st hint: You can use one of the Laser Connectors from "Behind the Iron Curtain" to connect the laser to the obelisk.
  
• 2nd hint: You will need another hidden fan in order to get the Laser Connector outside the puzzle area.
  
• 3rd hint: The fan itself is hidden nearby, outside the puzzle area, somewhere above ground level...
  
• Solution: In "Behind the Iron Curtain", use the fan and the two cubes to climb on top of the wall [Author's note: just like in the solution for getting the Fan to the obelisk] Look ahead, you should see a half-sunken stone structure. Jump across the pillars to get onto it. There's a fan, take it back to the puzzle area, and go down to the pit that has a Laser Connector, a cube and two pressure plates in it. Now place the fan on one of the pressure plates, the cube on the other, and the Laser Connector on the cube. Go up the ladder, take the Laser Connector from above, climb again on the wall, jump down, connect the Laser Connector to the obelisk, place it in front of the Slightly Elevated Sigil entrance, and finally route the laser beam through the doorway.

Activating the Laser Receiver - Pulviriza's solution

• 1st hint: You can use one of the Laser Connectors from "Behind the Iron Curtain" to connect the laser to the obelisk.
  
• 2nd hint: You can use the Jammer in "Me, Myself and Our Two Jammers" to open the elevated Blue Forcefield in "Behind the Iron Curtain" that is normally opened using two Pressure Plates.
  
• Solution: In "Me, Myself and Our Two Jammers" pick up the Jammer and take it to the Purple Forcefield entrance. You should be able to jam the elevated Blue Forcefield in "Behind the Iron Curtain" through the Purple Forcefield.
  
  Next, go in the puzzle where you just jammed the forcefield and get the second Laser Connector out of the pit with two buttons. Since the forcefield is being jammed open, you can also get two of the now three Hexahedrons back up. (Jump on the stack of two and get the single one out, then from the edge of the higher platform you can grab the second one from the stack of two.)
  
  You can now use the Hexahedrons with the fan to climb over the wall and take the Laser Connector with you outside the puzzle.
  
  Afterwards you can just use the Laser Connector to link the Obelisk Receiver to a Blue Source in one of the other puzzles. (Ex: "Alley of the Pressure Plates" - get the laser through the Purple Forcefield or over the wall.)

Where is it?

• Spoiler: There's no Star in this level.

How to get it?

• Seriously, look at the sign at the Level's entrance. No. Star. Zero.

Where is it?

• 1st hint: In one of the puzzles...
  
• 2nd hint: Beyond a Barrier with a Red Laser Receiver...
  
• Solution: It's in "Bouncing Side by Side", beyond a Barrier with a Red Laser Receiver, next to a Laser Connector.

How to get it?

• 1st hint: Like with other Stars, you'll have to get a Red Laser from one of the other puzzles.
  
• 2nd hint: You need the laser to go OVER the walls.
  
• 3rd hint: The Laser Source you need is in "A Fan Across Forever".
  
• Solution: In "A Fan Across Forever", after solving the puzzle normally, you'll need to stack three Hexahedrons onto the fan with a Laser Connector on top. First place a Hexahedron onto the Fan, then place the Laser Connector on top of it (Make sure to connect it to the Red Laser Source first!). Activate the Fan using the Jammer. Add a second Hexahedron to the wind, it should go under the first and push it up slightly. The third Hexahedron is in the room with the Sigil (Tetromino). Add it to the wind. Now go back to "Bouncing Side by Side" and use a Laser Connector here to activate the Red Receiver.

How to get it? - ElPhantazmo's alternate solution

• 1st hint: You'll need to use a Jammer in "A Fan Across Forever..."
  
• Solution: Atop the stairs in the puzzle "A Fan Across Forever...", facing "Bouncing Side By Side", you can place the Jammer slightly to the right of the pillar and jam the Star's forcefield barrier instead of opening it with the Red Laser.

How to get it? - [GofW] RibsNGibs's alternate solution:

• 1st hint: In "A Fan Across Forever..." you can use the three Hexahedrons on top of the stairs to climb the tall wall next to the stairs...
  
• Solution: In "A Fan Across Forever..." you can use the three Hexahedrons on top of the stairs to climb the tall wall next to the stairs. Take the Laser Connector with you on top of the wall and link it to the Red Source; you should be able to target it from "Bouncing Side By Side"... (This can also help you with the next Star as you can smuggle the Laser Connector out of the "A Fan Across Forever..." puzzle area.)

Where is it?

• 1st hint: It's not within the puzzle areas...
  
• 2nd hint: It's near the edges of the level...
  
• 3rd hint: Pyramid. Check it out.
  
• Solution: Go towards the Pyramid. The Star is on top of the huge arch-like structure here. Notice the Fan and Button in front of it?

How to get it?

• 1st hint: You'll need something from one of the Puzzles to hold down the button...
  
• 2nd hint: A Hexahedron would be useful here.
  
• 3rd hint: Get a Hexahedron from "Big Lump of Mine"
  
• Solution: In "Big Lump of Mine", after placing a Hexahedron on the first patrolling mine as you normally would to solve the puzzle, as you ride the moving Hexahedron, place the second one onto the right-most stationary Mine. Jump onto it, then jump onto the wall and grab the Hexahedron with you. Go to the Fan and Button and claim your reward.

Where is it?

• 1st hint: Explore around the island...
  
• 2nd hint: The star is beyond a Barrier, in some of the ruins around the Island.
  
• Solution: From the Spawn, facing the Castle on the smaller island, the Star should be in the left side corner behind you. The ruins closest to the sea in that side should have a Barrier with a Blue Laser Receiver.

How to get it?

• 1st hint: You'll need to get a Laser Connector from some nearby ruins (not in any of the puzzle areas)...
  
• 2nd hint: The Connector is guarded by a Turret.
  
• 3rd hint: The Connector and Turret are on the opposite side of the island - the right side behind Spawn.
  
• 3rd hint: The Turret can only be deactivated from within one of the puzzles.
  
• 4th hint: Deactivate the Turret with the first Jammer in the "Labyrinth" puzzle.
  
• 5th hint: You should now have the Connector, you need to connect it to a beam from another puzzle.
  
• 6th hint: The puzzle you need is "The Conservatory"
  
• Solution: From the "Labyrinth" puzzle you can see a turret to the left of the etrance, outside the puzzle. Disable it with a Jammer. Then go to where the Turret is and pick up the Laser Connector there. From the Star Barrier, head towards the opposite wall until there's a Wide Wall Window on your left. Looking through this window you'll see a smaller window to the puzzle "The Conservatory". Place the Connector Lens connected to the Receiver and looking at that smaller window. Go to "The Conservatory", use one Connector to open the way to the Blue Laser Source. Use the other two to connect the Blue Laser source to the Connector outside through the small window and the wide window.

Where is it?

• 1st hint: You should see it from the Sigil (Tetromino) area in one of the puzzles.
  
• Solution: In the "Ditch and a Fence" puzzle, you should be able to see it through the grate in the area with the Sigil (Tetromino).

How to get it?

• 1st hint: The only way to the Star is to jump the Fence...
  
• 2nd hint: You have all the tools you need to jump over the big fence!
  
• 3rd hint: It's just a matter of stacking things...
  
• 4th hint: Use your Recording and all of the Recorded objects you can to boost yourself over the fence!
  
• Solution: START RECORDING>Grab the Hexahedron, place it next to the big wall/fence behind the Ditch, opposite to the Barrier. Grab the platform and go into the Ditch. Wait around for 5-10 seconds, then jump onto the Hexahedron that you placed next to the wall.<END RECORDING> Now place the Hexahedron on top of the platform that your Recording is holding in the Ditch. Jump onto the Hexahedron. After your Recording jumped onto the Recorded-Hexahedron, jump over the fence! Now go get that Star!

How to get it using AnttiM's solution

• 1st hint: It involves a cube and leaving the intended level bounds.
  
• 2nd hint: Using the recording mechanic in "Rapunzel" you can climb onto the wall with a cube and go beyond the level's limits.
  
• Solution: In Rapunzel, record yourself carrying a platform from the loading platform to the outer wall, then put a cube on it, and jump on the cube. Jump on the wall and take the cube, then jump down to the other side. Then go right alongside the wall until you get to the rock formation, jump over the wall on the left, and continue to walk alongside the wall until you get into a small yard on the side of the church. Use the cube to climb onto the wall bordering the entry room of A Ditch and a Fence, and then move into the spot past the fence. Jump down and go get it.

Where is it?

• 1st hint: In one of the puzzles...
  
• 2nd hint: ...Beyond one of the wooden fences...
  
• 3rd hint: In the "Weathertop" puzzle area.
  
• Solution: In the "Weathertop" puzzle, after entering, turn left and look over the wooden fence that is slightly lower than the others around it. (Next to the Sigil (Tetromino) area)

How to get it?

• 1st hint: You'll need to stack three Hexahedrons next to the wall to jump over it.
  
• 2nd hint: They are all in this puzzle area.
  
• 2nd hint: You'll need a Blue laser to open the way to the third Hexahedron.
  
• 3rd hint: The only way to get a Blue Laser to open that Receiver is from another puzzle...
  
• 4th hint: In fact, two other puzzles are involved in opening the way!
  
• 5th hint: The other two puzzles are "Jammer Quarantine" and "Three Little Connectors... and a Fan"
  
• Solution (part 1): First, solve "Weathertop" and get two Hexahedrons, two Connectors and a Jammer next to the entrance. Place the two Hexahedrons next to the wall to the Star. Go through the gate where the Sigil (Tetromino) was, turn right and see the furthest Barrier with the Blue Receiver next to it. This is where you need to get a Blue laser. The Barrier after this one will be opened with the Jammer. Place one connector next to the wall opposite from the Blue Laser Receiver, place the second Connector linked to the first, and looking at the Puzzle entrance gate.
  
• Solution (part 2): Now go to the "Jammer Quarantine" Puzzle - place a Hexahedron onto the fan, place a Connector onto the Fan linking the Source to the Fan's Blue Laser Receiver; then activate the Switch to turn on the Fan. Next go to "Three Little Connectors... and a Fan" - Here you'll have to place a Hexahedron onto the fan, place a Connector linked to the floating Blue Connector from "Jammer Quarantine" onto the Hexahedron. Then use a second Connector to activate the Fan with the Red Laser. Now you can go back to the "Weathertop" puzzle and use the second Connector to link the floating Connector from "Three Little Connectors... and a Fan" to the first Connector (the one next to the wall opposite from the Receiver you want to open). Use the Jammer to open the second Barrier and finally get the Third Hexahedron. Use it with the other two to form a staircase over the wall and get the Star.
  
  
• Alternate solution, discovered by Nivomi There are two angled fans in "Weathertop". One has a bunch of metal fences, the other doesn't. Stack two Hexahedrons on the fan that doesn't have the metal fences, jump on the fan, and from the fan jump on the Hexahedrons. From them you can jump onto the wall. Take a Connector with you before doing so, and place it on the Wall, linking the Blue Laser Source to the receiver for the last barrier that blocks your way to the third Hexahedron. Afterwards just use the three Hexahedrons to make a staircase to the Star.

Where is it?

• 1st hint: In one of the puzzles...
  
• 2nd hint: ...Beyond a mysterious Barrier, but you can see it through a narrow window in a wall...
  
• Solution: In the "Oubliette" puzzle, past the barrier after getting the Sigil (Tetromino).

How to get it?

• 1st hint: A Red Herring is at work here...
  
• 2nd hint: You don't need to activate the Red Laser Receiver.
  
• 3rd hint: You'll have to boost yourself over the Barrier.
  
• 4th hint: Use the Recording mechanic.
  
• Solution: Solve the "Oubliette" puzzle normally. <START RECORDING> Get the Hexahedron next to the Barrier with the Red Laser Receiver. Now grab the Portable-Platform and stand next to the slightly elevated area to the right of the Recorder for a few seconds. Go back to the Hexahedron and jump on top of it.<END RECORDING> Grab the Hexahedron and jump on to your Portable-Platform-Carrying Recording from the slightly elevated stone plateau. When your Recording gets to the Barrier, jump over it while hodling the Hexahedron. Use the Hexahedron to open the second Barrier and grab the Star.

How to get it? - AnttiM's alternate solution

• 1st hint: You can activate the Red Laser Receiver.
  
• 2nd hint: You can use the red laser source in Armory.
  
• 3rd hint: You'll need to solve the puzzle first and then get the laser through a window.
  
• Solution: You have to route the laser through a window. Place one of the laser connectors in Armory near the entrance, and use another one to connect it to the source. Go to Oubliette, and place the cube to a spot near the entrance where you can see the target force field through a window and the connector in Armory. Take a laser connector, connect it to the one in Armory, and place it on the cube. Start recording, take the platform, stand beside the elevated area for a while, and then move next to the red receiver so that you can see the laser connector through the window. After awhile start the playback, grab the connector, connect it to the ghost connector and the red receiver, and place in on the ghost platform. Then take the cube, wait for the force field to shut down, place it on the right pressure plate, and get the star.

Where is it?

• 1st hint: In one of the other puzzles.
  
• 2nd hint: It is on a ledge above a Laser Connector.
  
• 3rd hint: You can find it just by stepping into the puzzle area and looking around, you don't have to solve the puzzle to see the Star...
  
• Solution: In the "Throne Room" puzzle, to the right of the first Laser Connector that you can pick up.

How to get it?

• 1st hint: Some platforming is involved.
  
• 2nd hint: Jump on things to get to it!
  
• 3rd hint: Use the Hexahedron to get to the stone pilar next to the up facing Fan.
  
• Solution: To the right of the Red Laser Source there is some raised stair like structure you have to climb using a Hexahedron in order to complete the puzzle. From the top of this structure, at the end further from the Laser Source, look towards the Fan with the Blue Laser Receiver. To the right of the fan there is a wall with a metal fence, and to the right of the wall there is a long elevated stone platform. Jump over to it. From there you should be able to jump at the Star and get it.
  
• Extra note about the solution (suggested by Vritra22189): If you're having trouble making the first jump, before climbing up first activate the Up facing Fan. When you're on top, drop the Hexahedron on to the Fan. You can then jump onto the Hexahedron and easily make the jump.

Three stars! Woah!
Sweet Sally, there's three Stars in this level! Since they're each hidden in a different puzzle, I'll just refer to them by the puzzle where they are hidden.

Where is it?

• 1st hint: Hidden beyond some walls...
  
• Solution: From the Entrance, go towards the Fan. See the wall to your right that, well, that turns right? It's behind this one.

How to get it?

• 1st hint: Just.. kind of climb the walls?
  
• Solution: Solve the puzzle, after grabbing the Sigil (Tetromino), go up the Stairs and just walk on the walls to the Star.

Where is it?

• 1st hint: Hidden beyond some walls...
  
• 2nd hint: You can see some Fan's wind effect where the Star is.
  
• Solution: From the platform on which you stand when placing cubes on the second patrolling mine, look through the metal fencing and see a fans' windy thing. That's where the Star is.

How to get it?

• 1st hint: You'll to get a ride for this one.
  
• Solution: Just place a Hexahedron onto the Mine, then ride it and jump over the wall to get the Star.

Where is it?

• 1st hint: Hidden beyond a metal gate. You can see it if you're paying attention while solving the puzzle.
  
• 2nd hint: Past a couple of Barriers...
  
• Solution: Past the Blue and Purple Barriers you can see it when climbing up the stairs.

How to get it?

• 1st hint: You'll need to think outside the box again!
  
• 2nd hint: Multiple puzzles are involved in fetching a Red Laser beam.
  
• 3rd hint: Notice anything that might help when you got the other two stars?...
  
• 4th hint: So the other two puzzles are "Time Flies" and "Up Close and Jammed"...
  
• 5th hint: First you lift the laser beam, then you bounce it off the ground.
  
• Solution (part 1): In "Time Flies" just get a linked Red Laser Beam on a floating Connector: Place the Hexahedron onto the fan. Place a connector linked to the Red Laser Source and Red Laser Receiver onto the Hexahedron. <START RECORDING> Grab Hexahedron, palce it on Button. Grab Connector, link Source and Receiver and place it on the Hexahedron that you've just placed onto the Button. Wait a couple of seconds. <END RECORDING>
  
• Solution (part 2): Now in the "Up Close and Jammed" puzzle, simply use one of the Connectors to link the floating Connector from "Time Flies" to the Receiver in "Dumbwaiter". Then go and claim your Star!

How to get it using Ipquarx's alternate solution

• 1st hint: With a bit of wall parkour, you can get the star using only the tools provided in the level.
  
• 2nd hint: You'll have to climb the stationary yellow Fan
  
• Solution: Solve the puzzle normally - get the two Hexahedrons and get one up to the yellow stationary Fan. Use the Hexahedron to climb the fan, then pick it up and balance it on the Fan. Jump on top of it, then jump onto the wall. From the wall you should be able to pick up the Hexahedron and use it to get over the wall into the Star courtyard.

How to get it using Dr. Mario's crazy solution:
Author's note: I don't even know how you managed all this. Impressive! I'm probably not gonna try it myself, but I figured I'd add it for anyone looking to try something less conventional.

• Solution: You need to bring three cubes into the main yard outside the puzzles: One from the "Dumbwaiter" puzzle area, one from the "Up Close and Jammed" puzzle area and one from the "Time Crawls" puzzle. You also need to get three connectors outside the puzzles.
  
  Then, you can use the three cubes to get onto the outer wall of "Time Flies". By jumping along the wall you can carry a connector to the outer castle wall that encloses the level. There is a point on it where you can actually link the connector to the receiver in "Dumbwaiter". Use the other two connectors and the one in "Time Crawls" to connect it to the Red Laser Source.
  
  Getting the cube from "time crawls" is pretty interesting. First, solve the level as normal. There has to be a floating connector, linked to the barrier at the end. Then make a recording that stands on one of the switches (not the one to the laser source) for about half a minute. Then, while the recording plays, remove the fan, place it on the other switch and step into the path of the laser source. THe floating cube will fall down for a short while. Run to it and grab the cube. Then just run to the exit while the barrier is still open and jump over the wall into the hub.

Where is it?

• 1st hint: In one of the puzzles, Duh! Ok it's getting kind of overly repetitive just saying this each time isn't it?...
  
• 2nd hint: You can see the star through Two Windows, in fact, you probably already have!
  
• Solution: The Star is beyond some extra Barriers in "The Seven Doors of Recording" and can be seen from "Circumlocution"

How to get it?

• 1st hint: Solve the puzzle first, then the answer should come easy enough.
  
• 2nd hint: Just use the Recording mechanics and Jammer.
  
• Solution: After Solving the puzzle, bypass the Barriers through the newly opened gate. Get the Jammer to Jam the first mysterious Barrier (the one to the right of the 7 Barriers). Then get the Connector and put it on the Button. Use the Recording mechanic and just chill around for like 10-15 seconds. End the recording, and while your recording is playing, go grab the Jammer and use it to open the third and last Barrier. (The recorded Jammer is already jamming the first Barrier.)
  
• Alternate Solution: You don't have to use the Recording Mechanic at all. You can just solve "Circumlocution" first and use the Jammer to open the last Barrier to the Star through the two Wall Windows - in the room with the Mine before getting the Sigil (Tetromino). Then go to "The Seven Doors of Recording", use the Jammer here to open the first Barrier, use the Connector to push the Button to open the second, and then just pick up the Star as you've already opened the third Barrier!

Where is it?

• 1st hint: Yea, should be easy enough to spot in one of the puzzles.
  
• Solution: "Dead Man's Switch" - Should be hard to miss.

How to get it?

• 1st hint: Honestly, if you've gotten all the Stars so far, you REALLY shouldn't need any help with this one.
  
• 2nd hint: Just, use the Connectors. All of them.
  
• 3rd hint: Instead of guiding the Blue beam through the Window, make it go around the wooden fences.
  
• Solution: Proceed with solving the puzzle normally, just make sure to open the Barrier to the Connector beyond the Window as you activate the Fan. After you've put the Hexahedron on the Switch, get the Connector out of the room with the Red Laser Source. (First use the Connector inside the Room to open its own Barrier, then use another Connector to re-open the Barrier through the Barrier itself and then get the Connector that is inside the Barrier-ed area). Now that you have 4 connectors, you can use them all to Link the Blue Source to the Star's Blue Receiver. (Just make the Beam go around the whole central fenced off area.)

Where is it?

• 1st hint: In the Messenger Island level in World C (The level behind the wooden barricade in World C)
  
• 2nd hint: Just go to the far right side of the Island and look for one of Uriel4's Messages on a Statue Bust.
  
• Solution: The Star is on the floating smaller Island in the Messenger Island area in World C. (In the right side of the level)

How to get it?

• 1st hint: The key is in Uriel4's Cryptic message...
  
• 2nd hint: "Two lovers are separated by the abyss of time and space. Yet true love knows no obstacles. -- Uriel4 v48.2.8552f"
  
• 3rd hint: As the message suggests, true love knows no obstacles, not even the abyss of space...
  
• 4th hint: I'll just quote some Gurren Lagan OST lyrics here: "Do the impossible, see the invisible! Row, row, fight the power!" (By which I mean there's an invisible path!)
  
• Solution: There's a narrow invisible path connecting the two statues - the one on the main land to the one on the small floating island.
  
  Stand in front of the statue on the main land and walk in a straight line towards the other statue. There's even a path in the dirt hinting at where the invisible path should be.

Where is it?

• 1st hint: Outside, as in on the surface, above the Hub Worlds.
  
• 2nd hint: Look around for a suspicious small building...
  
• Solution: Behind the Tower, in a grey building.

How to get it?

• 1st hint: You'll need two connectors and a Laser Source.
  
• 2nd hint: The Laser Source is more or less on ground level. The Connectors are not.
  
• 3rd hint: You'll need the axe to get to the Laser Source!
  
• 4th hint: The Connectors are in one of the Tower Level puzzles.
  
• 5th hint: You're supposed to get the Connectors from the Tower Level 1 Puzzle area.
  
• Solution (part 1): Facing the tower elevator, turn left and go around the tower. On its left side there is a boarded off area with a Laser Source behind it. Break the boards with the Axe from the World C Hub.
  
• Solution (part 2): As for the Connectors... In the Level 1 Puzzle, in the Tower, go in front of the Barrier that blocks the way to the Terminal, but instead of trying to open it turn left and look in the corner here for a gap in the fence. Take the Connectors through the gap all the way back to the Red Puzzle Gate. Then just kind of, drop them over the edge (or take them down with the elevator if you wanna be like that.) After you get both Connectors on the ground, just use them to open the Barrier to the Star.

Where is it?

• 1st hint: In the Tower. You can see it through a fence...
  
• Solution: In the Tower Level 3 Puzzle area, you can see it through a fence on the left side of the area.

How to get it?

• 1st hint: You'll have to take a leap of faith to get to this one.
  
• 2nd hint: The way to the Star is from above.
  
• 3rd hint: I mean, you'll have to literally drop through the roof!
  
• 4th hint: The drop point is on Level 5 of the Tower.
  
• Solution: After opening the Red Sigil (Tetromino) Puzzle Gate on Level 5, just go forward and gaze down from the window (big opening in the wall). You'll see some small ledges you can stand on. Jump down to them, or rather walk down to them. Go towards the outwards pointing metal beam, and walk off it's very tip. You should fall right through the window leading to the Star!