Thank you for playing!
-Bats (batbird mutants, lol) can be hard to spot indead, I'll think how to fix this, I don't really want add visible eyes to them for now though.
-Yes, goblins can die on spikes, and cultists don't as they know those traps very well (those goblins are kind of drugged by cultists, so they don't think with a clear head).
-As for flames that is something like faction related damage, but cultist can burn bats, and poisonous bats can spit on cultists (if mobs get in the way of each other attacks), as bats don't have faction, usually they don't attack cultists for no reason 'cause they got used to see each other.
-Power Charge of fighter gives you ability to strike (if weapon attack pressed in process and you have enough power points) for extra damage to a few targets (default - 2 targets, with Mob Slayer upgrade - up to 4 targets), and I will add more sweep melee abilities later in development.
-Yay, thank you for this bug report, I do catch some strange bugs from time to time when trying to create a new char at camp with new save files, thought I fixed it already, lol.