Dobro, tovarish!

This build is for calm destruction. Light on left hand action, heavy on the faces of cosmic bosses.

Damage

His basic  with these IP brutes for over 450k. At about 2000 IP you can transition to  but it needs a load of spirit and health to be competative before then. His basic is the bulk of his damage, with  and  to add in some excellent burst.

  is on RMB as it is very easy to miss due to small position differences or latency on regular keys. Expect executes over 1 million when you are finishing a boss.

His signature  is an impressive 5 million brute, however in testing it was not worth over-investing in cost reduction to reduce its cooldown, only that from IP and the 2 cosmic affixes; cost reduction and signature cooldown reduction. The activation cycle is to hit your med kit to activate (the buff is 30 seconds, the sig cooldown is less, so it should be up all the time), then  to max your health and then . Thanks to the last two talents this combo hits at its maximal damage range.

With 20 points in  the ultimate has a 7 minute cooldown, so you get to use it on almost every other boss wave on patrols. 100% brutal hits for 30 seconds will almost wipe out a solo Sinister 6 wave on cosmic, leaving badly battered baddies to be quickly mopped up.

Finally there is  a misunderstood skill, and not as widely appreciated as it should be. Its damage is modest which is why it is overlooked, but it is spammable and more importantly stuns enemies. You can maintain large packs in constant lockdown, trivialising encounters with many mobs. Position yourself and fire away. This tactic made passing the cosmic trial on day 3 of the new server with hardly any IP and terrible gear very easy.

Defence

Colossus is the strongest tank in the game. This does not come from defensive gearing or IP. His armor mechanic absorbs absurd amounts of damage before even touching his 100k EHP.

Armor is maintained be having multiple sources of spirit recovery layered in places where you are not losing damage: Catalyst spirit on hit rather than health, his basic has huge health on hit already. Deadpool Team-Up Away is his tankiest buddy with 5 amor per second when you are not using armor spending abilities. Its a left-over from Colossus' uncompleted BUE remake when his abilities did cost power, now its free armor!

Gearing

Transitioning to  from  costs a huge amount of attack speed loss. You need to make it up wherever you can. Full investment in attack speed and a nice insignia go a long way to making the difference. If you are making a new Colossus be sure that you can access these boosts or you will find your TTK is much worse than sticking with his own slot 1.

 is also important. His only vulnerability comes from  which when talented ends up with a longer cooldown than its duration. Cobra solves this annoyance.

 is an excellent alternative medallion. Its not much less damage than  and the spirit regen is very noticable. Strongly recommended for building a new Colossus.

Now go forth and crush like Colossus!