Also known as: 温泉開発部, 温泉開発部のモブ
Sprites and mobs in Blue Archive meant to represent the bulk of Gehenna Academy's Hot Springs department, they have 3 variations of the mobs featuring Green Hair, Blue Eyes and Beret, the second (and probably the common) one has Silver Hair, Hard Hat, Gloves and wielding a Sledgehammer. the third one is the same as the second one however has Blue Hair and is longer.
These mobs are specialized in Demolitions and creating certain Hot springs in different academies. Their first appearance is from Operation Record of No. 227 Hot Spring Resort.