Higher Intelligence allows the player to earn more XP from doing tasks, which means that they will level up more quickly. It also increases the player's mana point (MP) cap.
Once the player's maximum MP is over 100 (requiring Intelligence 35 or greater), their maximum daily mana regeneration rate becomes ten percent of their maximum MP, instead of a base 10 MP every Cron. Their mana gained from positive Habits becomes 0.25% of their maximum MP, instead of a base 0.25 MP, and mana gained per Daily, To-Do or To-Do checklist item becomes 1% of their maximum MP, instead of a base 1 MP.
Mages can buff their party mates' INT by an amount determined by their own unbuffed INT using the skill Earthquake.