In Persona 3 Reload, unlike the other cast in the game, the main character’s Theurgy varies and is unlockable by fusing certain personas and unlocking them in your persona compendium.
Build the Character’s Theurgy By Using Skills
The fastest way to be able to use Theurgies is to keep on using the main character’s personas. Thanks to the nature of the main character’s Persona, it’s highly recommended to aim for enemy weaknesses by changing your persona to match the enemy’s! This will allow you to cast two personas per round which will hasten your Theurgy Gauge’s charging rate.
