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Intelligence determines how well your character learns and reasons. This ability is important for wizards because it affects their spellcasting ability in many ways. Creatures of animal-level instinct have Intelligence scores of 1 or 2. Any creature capable of understanding speech has a score of at least 3. A character with an Intelligence score of 0 is comatose. Some creatures do not possess an Intelligence score. Their modifier is +0 for any Intelligence-based skills or checks.
You apply your character's Intelligence modifier to:
- The number of bonus languages your character knows at the start of the game. These are in addition to any starting racial languages and Common. If you have a penalty, you can still read and speak your racial languages unless your Intelligence is lower than 3.
- The number of skill points gained each level, though your character always gets at least 1 skill point per level.
- Appraise, Craft, Knowledge, Linguistics, and Spellcraft checks.
A wizard gains bonus spells based on his Intelligence score. The minimum Intelligence score needed to cast a wizard spell is 10 + the spell's level.