>>535409924
Pipilpan Idol's hat phase doesn't render it immune to the elements that aren't being shilled, it just has somewhat high resistances to 5 out of 7 elements. If it wasn't because everyone were using their good characters across the two other bosses in Stygian Onslaught I'm sure many people also could have killed the SO cactus without needing to resort to taser teams
I assume Hoyo themselves also realised this at some point during development because the 6.0 electro-charge shill boss is even more reliant on you bringing electro along to pause its shields' regeneration