Mana is a numerical stat that determines how many castings of a spell the player can achieve. Each spell has its own Mana cost, and the more powerful the spell, the more Mana it will cost. If the player has the Phosphorescent Pole on their person, it will regenerate Mana slowly, as will any weapon upgraded down the Crescent path. Additionally, Fresh Spice and Old Spice will restore Mana. Finally, attacking any NPC or enemy with Geri's Stiletto will restore some Mana to the player.
Mana is gained by increasing the Intelligence stat.