Quote Originally Posted by Kevee View Post
Because SF is more DPS than Ruin/Ruin II, even when boosted with RS.

Mine hits for 90/100.
Ruin/Ruin II crits for ~300-310 without RS. That means ~360-370 for crits during.
You lose ~3 ticks by casting it so late, which is 270-300 damage.
That's more than the damage you gained using Ruin/Ruin II instead.
I believe the confusion is to why you just wouldn't cast it before RS, so that you then don't have to lose any time on a spell not affected by the buff. Your discussion of potency doesn't address this, it just makes the case that in normal situation SF has priority over ruin, which is super true.
Cast SF first, it should still be up by your second fester, after which you are free to cast it again. Or am I missing something?