In Zariel's Challenge (Master), once the team enters the fight after waiting 5 seconds on the purple circle, there is a very high chance that the Lifespark from a Soulweaver will simply disappear (happened 3 times in the 4 runs I did today).
If that happens, any powers/feats that depend on the Lifespark won't work (including the Tab heal, the Soul Reclamation feat or the Soul Barrier daily). Warlock's Bargain can be used as a workaround to get the Lifespark back, but it is quite clunky.
Also, some companions die at the entrance and never come back. I've seen it happen to the Black Death Scorpion and to Zariel (the companion), but it probably affects some others as well.
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