It appears monsters on quests are now taking damage from area effect that before only the player would take. For instance, fire traps burn them, that would otherwise only bother pcs, and acid hurt slimes in another quest where they were usually immune.
Can you name the quests?
I believe this was happening as well with monster AoE's in Machine Core 34AB. The Gas Animatrons will basically indiscriminately AoE everything to death.
The Purple Crystal quest (acid pool slime variant), and Bloodtail Cove.
Goat quest with steam areas.
All should be fixed next reset.
Thanks!