Spirit is the main currency used by characters. Characters' spirit pips replenish their spirit over time.
Spirit can drop below 0. The UI will read 0 until the character recovers enough spirit.
Characters have spirit (float) and max_spirit (float).
Characters' spirit, by default, is calculated as 20 + spirit bestowed by their current job + spirit bestowed by their current equipment.
Armsmen have 10 extra spirit; Brawlers and Tamers have 20 extra spirit; and Chemists, Disciples, and Hackers have 30 extra spirit.