This is the guide about making your character as linear-powerful as possible, and about summoning lots of minions. If you like grenades or turrets or other personal roleplay preferences - guide may not be exactly for you, however, some parts can be adapted in almost any gameplay.

The build uses ideally only one type of summon, focuses on popular lightning damage and requires only one action bar to play, as well as little fuss with powerups.

Your LMB and RMB skills are Supercharged Blast(SCB) and Pocket Mechanoid(spider) respectively.
Both should be maxed with all available upgrades(1 for SCB). Only SCB uses rage and should be used with Hypercharged Blast for virtually double damage.

Your primary support ability will be Elyctric Sphere, which should be maxed with both upgrades.
With maxed Cooldown Reduction %(CDR), it will have 8.8sec CD with 4.8sec duration, over 50% realistic uptime.
This is the skill that gives you inifite Mana, makes you invulnerable and heals you to full(if possible) and gradually reduces your CD times(even below their capped CDR). You can not attack with this skill, but you can:
-Deploy 6-8 spiders per use
-Use Ghastly Shape to move

You secondary support skill is Force Armor. It shouldn't be really invested in, as you won't be using it for damage and absorb isn't that important with relatively small cooldown. Just try to refresh it as often as possible and you should have almost constant defensive bubble.

Optional support is Ghostly Mirage. If your Katarina is nothing, but a MF or Dexterity bot, then this skill won't do much good and should probably be omitted.
If Katarina is built for at least 30k dps, you could get some extra with just the first rank of this skill. With capped CDR, duration CD are the same - 24sec, and with Elyctric Sphere, you shouldn't have problems re-casting it in advance.
I do not recommend to build Katarina as endgame tank, because this skill would be useless with low %hp clones, and you won't have a lot of points to invest here with this build.

Finally the great utility comes from Ghastly Shape. 8 sec CD capped, it is both a dash that is faster than any speed bonuses and a great combat mobility tool.
The best thing about it, is that not only can you use it in Elyctric Sphere, but it also enables you to move freely afterwards. Glitch or not, it sure comes in handy.

Reaching Class Mastery 100% is important, because it gives good milestone bonuses(30dex and 10% damage at 90 and 100 respectively) and increases the damage of your skills(SCB and spiders). To achieve it, you will have to drop a lot of tricks/auras and use the points in cheap Grenade Lob and Phlogiston Torch), but in the end - it's still more useful than other options.

Passives:

>Rage - maxed with both upgrades. This skill greatly extends the uptime of your Hypercharged Blast power-up for your SCB, and therefore directly contributes to increasing your dps.

>Defensive Synergy - maxed with both upgrades. Second upgrade, Self-repair mechanism, is a very cheap and sustainable way of healing your spiders against mild AoE.

>Offensive Synergy - maxed with both upgrades. Drain Accessory virtually gives your spiders lifesteal and greatly improves their durability. Steel Springs allows your spiders to maneuver faster in the battle.

>Protective Synergy - maxed with at least first upgrade. 20% summon duration is one of your major sources of duration bonuses. 10% CD reduction is also good, but once you get 55%+ global cooldown reduction, this mastery becomes limited or even obsolete.

>Improved Remote Controller - maxed with both upgrades. With the amount of spiders you will be able to deploy, even 15 is a small number, so maxing this skill is crucial, while the masteries are quite contributing.

>Greasethumb - maxed with both upgrades. Big, direct upgrade to your summons. Accidental Supercharge makes 1/10 spiders a killing machine, while Spontaneous Reconstitution is one of the ways to passively recreate spiders.

>Paradox Recombination - rank 1+. Theoretically you could invest more points to the current cap, but there is little use for it in the endgame. When you can rapidly deploy waves of spiders, midfight reconstruction isn't so important.


Auras:

>Storm Adept - rank 10. You don't need the first upgrade, since Elyctric Sphere resolves any mana issues, and second upgrade also becomes obsolete as you reach GCD cap.

>Mechanoid Building - rank 1+. Rank 1 will already occupy your aura slot to it's best extent. Maxing it and taking Robust Mechanoids mastery is also a big plus, but it's not the top priority on the list, biggest stats and survivability your spiders get from class passives. Spending 2 points per rank here is a bit too expensive.

>Clockwork Expertise - rank 1+. Likewise, investing here is optional, masteries are useless(2% reconstruction chance is insignificant), duration is good for rank 1 and is easier to augment by other means and gear.

Perks are a brilliant and simple customization mechanism of Van Helsing. So much can be done for so little cost.
Please, take a look at: Gamebanshee's list of perks[www.gamebanshee.com]. It will explain what to get and how, while I explain why.

1. Cooldown reduction perks(from willpower):
Focused, Focused II and Enlightened. 1/3 of your total needed CDR to reach the cap is available from these perks alone.

2. Critical hit perks(from luck):
Perfect Aim and Perfect Aim II. Highest DPS per perk and an important part of your Critical Chance cap mixture.

3. Lightning damage:
Elyctrician, Thunder God and Elementalist. Direct improvement of your damage.

4. Arcane Mechanic perks:
-Extended Durability is one of the most accessible upgrades to minion duration.
-Weird Scientist is great when you are constantly redeploying spiders.
As a special note:
When Weird Scientist and Accidental Supercharge mastery of Greasethumb combine... you get one infenal mechanoid. My personal record was something around 200k per hit mechanoid.
-Sublimated Discharger - additional weapon enchant can play crucial roles in your build, and on top of that - you can take your best weapon roll, enchant it, drop the perk and still enjoy the results.

5. Skill perks:
Master, Master Hunter, Veteran Hunter and Fortune's Favored Son, Teacher - you will have to take all these if you want to reach Class Mastery 100% and have something left for anything else.

6. Utility perks:
The Flash - 10% movement speed is handy, but optional speed bonus.
Second chance - if you aren't hardcore, it doesn't hurt to avoid being hurt.

This build revolves around Chrometrooper(CT) Set. 3p set is very powerful for DPS and cooldown reduction, while 4p is good enough dps to take it even over godlike boots.
Note:CT Cannon's damage is somehow bugged, it's around 120-130 base, while normal 60 dischargers are 80-90. Not that I complain.

The stats you should look out for:
Dexterity, Lightning Damage Boost%, Lightning Damage Bonus, Minion Damage%.
Optional - Minion Duration(present on CT chargerpack), Full Heal on Hit(present on Garb of the Vampire King). Duration will never hurt, and Full Heal is crucial for scenarios with "no healing" condition.

-Dexterity is your god-stat, 1% weapon damage per point(which scales spiders as well), 1 dodge. No item should be without standalone dexterity enchant.
Note: all sources of "damage% boosts(perks like Slayer or Fine Tuning), amulet enchant and such - refer to some miserable %bonus of melee and ranged damage. Basically 1% of "damage" is like 1 body and 1 dexterity, only excluding side benefits. It's so low that it's not even remotely considerable over things like 50 dexterity or 10% lightning damage.
Your hard-point Dexterity should not go over 300, as spending 2 points for one is a big waste.
Essences must be exclusively Dexterity, unless you need CDR% to reach 50%+.

-Lightning damage % boost is direct upgrade of your Supercharged Blast's default damage. Which is a LOT. Basically... I am not mathematician, but I believe it works like this:
Your default SCB damage is a big modifier of weapon damage(518% current max), all the dexterity modifier of ranged damage and "damage%", additional damage types, like lightning bonus damage, ice, poison. ALL of this becomes lightning damage and is increased by up to 10% per item.
Should be enchanted on CT Cannon, CT Helmet and CT Chargerpack and runecrafted into Trophy, Amulet and Rings.

-Lightning damage bonus isn't different from ice/poison small bonuses(they don't get modified by dexterity, and so are MUCH weaker than "weapon damage %" or bonus), except for it is also added to the damage of your Pocket Mechanoid's default lightning attack. Therefore it's a priority over other elemental bonuses.

-Minion Damage% - pretty much the same as Lightning Damage Boost% for you. The FINAL modifier to calculated damage.
Should be enchanted on CT Cannon and is present in CT Chargerpack. CT Helmet will be your personal choice: to use the enchant slot for Lightning Damage boost% or Minion Damage%. Since LDB% doesn't affect spider's damage, it's either you or the spiders.

-Body - secondary stat after your hardpoint Dex reaches 300. Gives you hp, defense, scales spiders' hp.

-All resistances - usually present on epic/godlike gear, must be enchanted in Trophy.
-%DamageReductions(good when you reach 1500+ resistances)
-Item Defense(probably best enchanted only on Garb of the Vampire King)


Cappable stats:

NEVER enchant Critical Damage. One point of Luck gives 1% CritDamage and is usually rolled higher than Critical Damage. When you get plenty of godlikes and custom gear with +allstats or enchanting slots, you will likely reach Critical Damage cap of 450% without any further effort.

Critical hit chance is capped at 50% and is the biggest DPS modifier among stats. As such, you should calculate all of your possible sources of critical hit chance(weapon essence, enchants, elixirs, glory etc) and try to stay as close to the cap as possible.

Hardcap of CDR is 60%, everything past that is wasted. Softcap is 55%, as you really won't notice the 5% difference. Reaching 50-55% is already considering your build complete.

Crit chance and CDR are found on essences, items, enchants, perks, set bonuses and even Elixirs(post-cap). Find your own mixture to reach the hard caps.

The most important trophy is the Adamantine Rotator. It reduces enemies' resistance to your damage at the cost of rather unnoticeable speed. Basically, resistant enemies will take full damage, immune enemies will take most of the damage(and no longer impair your build). This is the highest priority for stable farming.

Second best trophy is Tribal Totem. 10% lightning bonus is yet another layer of lightning %, and you don't pay 33% physical resistance just for it(although it would've been worth it) - you also get elemental resistance. Just re-balance your resistances and enjoy 10% more damage.

Third trophy is utilitarian. I recommend Shackles of Pain for MF. With your damage, there really is no downside, and for some reason it gives more than 100%. You could take Oaken Heart, Special Find, but I'm not sure if it affects anything worth farming.

If you want to purely minmax your damage, you can take Shadow Blade. However, it's a very troublesome choice. You crits may become even heavier, but enemy gets around 20% dodge chance. It affects everything: your spiders, your SCB's AoE. What previously could've oneshotted a pack of enemies - might oneshot only half of them. Besides, with your damage, it takes you 1-3 hits to kill an enemy, and this Trophy won't reduce the odds, it will only increase the overkill damage.

Your spiders will allow you to never engage anything directly, staying out of nasty spikes, fire, reflective shields and the rest. If anything goes south, Elyctric Sphere and Ghastly Shape will always get you out of trouble, Force Armor will always absorb some excessive damage, Second Chance will do exactly what it says... And if you aren't hardcore, dying shouldn't be that often or scary to sometimes afford yourself.

Your Charged Blast will deal tremendous AoE damage in two instances: projectile and explosion. Attacking certain big bosses can trigger effects of both instances, effectively doubling your damage.

Here is the updated video guide with my ugly voice. It explains in a bit stuttered depth everything from the guide and provides yet another laughable presentation.

And here's a the public build demonstration:
P.S.: If russian players have any questions, they can be asked in the comments.

May the RNGesus be with you!

(Maxed - 10+2upgrades)
Grenade Lob LMB Maxed + Summon Mechanical Aide RMB Maxed (Self-Winding Mechanism power-up)
Elyctric Sphere Maxed, then Rage+Defensive Synergy Maxed. Cheap defense with basic regen, Rage will allow you to spam self-rebuilding spiders.
Tricks/Auras do not matter until 60, then up to you, as long as Storm Adept is 10.
When Fulgurous Discharge is unlocked - drop all points from Grenade Lob and change LMB to Fulgurous Discharge, keep leveling it, no power-ups.
Remaining points should be used to Max Offensive and Protective Synergy.
When Artillery is unlocked, you can move points from Fulgurous Discharge to Artillety(no need to max, veteran skills are vastly superior).
Upon unlocking Liquid Fire in veteran game - change all Artillery points for it, again no need to max. Do the same for Canister Shell when it's out. Bullet Barrage is too expensive to be interesting. You should be fine with 5+ Canister Shell. Use all remaining points to Max Improved Remote Controller and Greasethumb.
When SCB is unlocked - proceed with the guide.

A youtube commenter asked about this incredible duration, I took a look at it - it appears that 4-piece bonus on Chrometrooper pack is bugged and is not ~20%, but helluva lot more. I had Extended Durability perk, removed Protective Synergy upgrade - was 57 seconds. Removed Chrometrooper Pack - went down to 28 seconds. Yet another reason to focus on 4-piece Chrometrooper set, ignoring Demonfeet.

Totally forgot to do it in time - here's the Katarina build: