Faster than a Speeding Arrow

Achievement is rewarded when defeating Thulsa in Dreadspire without hitting balls from devices on sides of room.

Guide
is in Dreadspire in his spider form. Occasionally devices on side of room start shooting damaging balls across the room (similar mechanics like in Balder's Temple boss with transparent walls). Achievement is granted when you're not hit during the fight.

Thulsa boss is removed from new 10-level Dreadspire. It's unknown if this boss fight returns.