Compiled by the team effort of the inkle discord, with special thanks to PVB who compiled a spreadsheet! The most recent version can be found here: https://docs.google.com/spreadsheets/d/1-dIvpbr0oRPz1HuAMBeq4v5HflzFF8Fr_Frz2Mfrw2o/edit#gid=0

Blessing peaks is done by leaving an object on the peak. On your first run through the game, many peaks will not present the option to leave an object (although some do,) but in a New Game + they will. Most peaks have many possible objects they will accept, and some have objects which give a special response in addition to (or instead of) the blessing. When you bless a peak, the weather will turn sunny, and you can heal up to your absolute maximum health, even if it had been reduced by sleeping rough. (Although watch out, there is a bug waiting to be patched where rarely doing this can reduce your max health.)

This peak will accept:
Rusty Blade
Bottle Top
Sheep's Jawbone
Glass Fragment
Razor Blade
Tuna Can Lid
Metal Barb
(And probably anything else sharp enough to shave with...)

This peak will accept: Sheep's Jawbone, Small Sharp Tooth, Cow's Tooth

This peak will accept: Playing Card, Thistle Flower, Crow's Feather

This peak will accept: Fisherman's Knife, Bronze Dagger, Spectacles, Eye Patch, Razor Blade, Glass Monocle, Broken Whistle, Glass Lens.

This peak will accept any feather, or the winged brass pin.

This peak will accept: Wooden Rung, Climbing Clip.

This peak will accept any gold item, or barley grains. It will transform the item you use into a golden flower, which you can then pick up - the peak will stay blessed, and you can use the flower for another place that wants gold.

This peak will accept: the Rabbit's Foot, the Playing Card, or the Dice

This peak will accept: The Tiny Bell, the Cowbell, the Broken Whistle, or the Flute.

Here the item doesn't matter, but you need to sit down at the small rock to the left of the peak. It will make you think gloomy, negative thoughts. You need to pick positive responses and then stand up, and the peak will be blessed. Some people have reported success using the Grass-Reed Boat here, but I couldn't get it to offer when it was in my inventory, so I think the sitting down part is what matters and then the peak will take any object.

This peak will accept: the Thistle Flower, the White Rose, the Short Sword.

This peak will accept: any feather, or the Winged Brass Pin.

This peak will accept: Top Half of Fishing Rod, Grass-Reed Boat, the Seashell, the Bottle Top.

This peak will accept: Gold Wedding Band, Thistle Flower, Lavender Sprig, Yellow Broom.

This peak will accept: the Wedding Band, the Wild Rose, Yellow Broom, Lavender Sprig.

This peak will accept: the Leather Glove, or the Metal Nailfile.

This peak will provide a map if you use the Bottle of Whisky or the Half-Full Hip Flask. For blessing, it will also accept the Whisky Cask or the Whisky Barrel.

This peak will accept: Wooden Butter Knife, Cowbell, Leather Glove, Cow's Tooth

This peak will accept: the Carved Stone.

This peak will accept: Plastic Astronaut Figure, Crescent Moon Earring, Glass Lens.

This peak will accept any gold item.

This peak will accept the Bent Fork, the Pickaxe, or the Chunk of Coal.

This peak will accept a Pine Cone.

This hill will become blessed after you light the two beacons. The first one is down and left of the peak, and you need to offer some way to light it to the girl - the tinder box, cigarette lighter, etc. The second one is at the peak, and you need to put flammable items in it (at least two) and then light it with something - if you don't have one of the more obvious fire items, you can light it with a small stone, but it may take more than one try for Moira to succeed.

This peak will accept: the Monocle, the Spectacles, the Eye Patch, the Glass Lens

This peak will accept the Eagle Feather or the Massive Quartz Rock, and the eagles will then pick you up and take you on a little trip. The peak will stay blessed after this, but the quartz rock will reappear at random locations in future runs and you can place it again for another eagle ride if you wish.

The Lavender Sprig will bless the peak and then helpfully sneeze you forward.

This peak will accept: the Pocket Handkerchief, the Pocket Mirror, the Wooden Butter Knife, the Boot Lace, Dice.

This peak will accept: the Twisted Bit of Metal, the Rusty Barb, the Tent Peg, the Glass Fragment, and any knife or blade.

This peak will accept any feather.

This peak will accept: any tooth, or the Hard-Boiled Sweet.

This peak will accept: Rabbit's Skull, Rabbit's Foot, Sheep's Jawbone, Bent Fork, Winged Brass Pin, Deer Antler, Small Sharp Tooth.

This peak will accept any metal item, your torch, or the Purple Crystal.

This peak will accept: the Bronze Dagger, the Roman Coin, the White Rose, the Golden Brooch, the Thistle Flower.

This peak will accept: the Grass-Reed Boat, the Seashell, the Chunk of Green Seaglass, the Top Half of a Fishing Rod.

You must have blessed every other peak first, and then you can leave Moira's torch to bless the lighthouse.