Intelligence measures mental acuity, accuracy of recall, and the ability to reason.
Intelligence Checks
An Intelligence check comes into play when you need to draw on logic, education, memory, or deductive reasoning. The Arcana, History, Investigation, Nature, and Religion skills reflect aptitude in certain kinds of Intelligence checks.
Arcana
Your Intelligence (Arcana) check measures your ability to recall lore about spells, magic items, eldritch symbols, magical traditions, the planes of existence, and the inhabitants of those planes.
Engineering
Your Intelligence (Engineering) check represents your training with the design and construction of machines, buildings, and structures. You make an Intelligence (Engineering) check when you design or build a new machine or structure and when you evaluate the design and construction of such things.
Wizards add Engineering to the list of skill proficiencies they can choose from during character creation. The Engineering skill is also available to any character with the Professional (Academic) or Sage background.
History
Your Intelligence (History) check measures your ability to recall lore about historical events, legendary people, ancient kingdoms, past disputes, recent wars, and lost civilizations.
Investigation
When you look around for clues and make deductions based on those clues, you make an Intelligence (Investigation) check. You might deduce the location of a hidden object, discern from the appearance of a wound what kind of weapon dealt it, or determine the weakest point in a tunnel that could cause it to collapse. Poring through ancient scrolls in search of a hidden fragment of knowledge might also call for an Intelligence (Investigation) check.
Nature
Your Intelligence (Nature) check measures your ability to recall lore about terrain, plants and animals, the weather, and natural cycles.
Religion
Your Intelligence (Religion) check measures your ability to recall lore about deities, rites and prayers, religious hierarchies, holy symbols, and the practices of secret cults.
War
Your Intelligence (War) check measures your acumen with tactics, strategy, and military operations. You and an opponent may make opposed Intelligence (War) checks when playing a game of strategy or leading armies on a battlefield. An Intelligence (War) check can also give you additional information in a combat situation.
Fighters and paladins add War to the list of skill proficiencies they can choose from during character creation. The War skill is also available to any character with the Soldier background. Bards can choose the War proficiency and any human can choose War as their bonus skill.
Other Intelligence Checks. The GM might call for an Intelligence check when you try to accomplish tasks like the following:
- Communicate with a creature without using words
- Estimate the value of a precious item
- Pull together a disguise to pass as a city guard
- Forge a document
- Recall lore about a craft or trade
- Win a game of skill
Spellcasting Ability
Scholars and Wizards use Intelligence as their spellcasting ability, which helps determine the saving throw DCs of spells they cast.