6* dual crystal
Since there's no 7* Archangel I've decided to save 6* shards and only open the mutant/skill dual crystal to give my self a slightly better chance.
Are they on a set day rotation or random?
I remember back when act 5 first came out there was a path with a really annoying Antman that had really annoying nodes that combined with his glancing you could barely damage him unless with dot effects.
He also wasn't poison immune (not sure when they added that).
Anyway I was stuck there for months until I got 5* AA and he just melted that Antman, plus I really like AA in general.