It feels like just yesterday that I was asking the forum how to get Uncollected. I've done my progression in spurts of a few days. It's always I'm stuck on something for a month or so, then I get a good pull, use all my boosts, and work into the next milestone. I recently completed act 5, and have been stuck on 6.1.6. For reference, this is my roster:

On 6.1.6, I'm taking the Agent Venom path and then going left to the Red Skull. Mags destroys everyone on that path except for Gambit. I've gotten to the Sabretooth boss with all my champs with 80% or more health, but I can't get him very low because of the stupid regen. (Side note: why can't he be a metal sabretooth?) Any tips on how to beat him, and then how to get to 6.1.6 with my current roster. Also: you can't see it, but that Void is going to get to 4/55 and 50 sig in the next few weeks.