Shackler can spawn fused to an Angelic Voidlord. This makes it immune to damage from attacks, spells, and indirects, so… everything. It’s a netherboss so it can’t be insta-killed either.
I wonder if all the things that say ‘Immune to whatever’ shouldn’t be changed to just reduce damage by 99.999% or something, because this sort of thing seems to happen quite frequently. Would be nice if once you hit 10000+% exhaustion you could still potentially win the fights like this, wouldn’t it?
Although then you could theoretically win fights like this through some cheesey method… but is that really a big deal in a Single Player game? One of the things that makes Siralim great is how easy and fun it is to just ‘break’ the game with combinations.