@AndrlCh said in Question about which s-grade augment I should take for my Atlas ex katana.:
In most cases, Lifesteal on its own is more than enough to cover you, and the other slots should be more focused on damage-based S-Grade Augments, particularly Precision Will since Braver and Phantom focus on Critical Damage (S1, S2, and S3 Precision Will means an additional 10% damage multiplier on Crits).
Regardless of your choices in S1-S3, from my understanding Rainbow Adversity will only kick in if you take an additional 500 damage after Seagleam activates within its 30 second window, meaning you don't get an instant heal from activating Seagleam and it only has a limited window to activate; contrast this with Lifesteal, which is 30HP per hit per target, meaning that when mobbing, you will more than likely be constantly at full HP, and a multi-hit attack on a boss can easily heal you quickly, especially if your Mag has the Dance SP Action. Plus, ideally you should be avoiding taking that much damage (either by Countering as a Braver or Dodging as a Phantom), so Rainbow Adversity is way more situational.
That said, if you want to try out both for yourself, don't forget that you can grab a Novel Weapon to act as a storage weapon for S4s, so you can always use the S-Grade Augement Transfer option to have both ready to test.
Oh thanks a lot for clarifying about rainbow adversity that it doesn't activate with seagleam. But going precision will 3 times isn't it better to make one of them at least something that increases crit chance since I'm maining Phantom now and as far as I know Phantom's crit chance isn't that high to begin with?
Btw S1: Precision Will is 3% crit damage, why shouldn't I take S1: Augment Will instead which gives me 4% damage all around?