The mental trait marks effects that directly alter or interact with a creature’s mind—their thoughts, perceptions, or will. A mental effect has no effect on an object or a mindless creature; constructs, undead, or programs with the mindless trait are explicitly immune to mental effects unless an ability overrides that immunity.

Mental is a category trait, not a damage type by itself. Many mental effects also deal mental damage, to which mindless creatures and those with immunity to mental are often immune. Traits like emotion, fear, and possession sit under the mental umbrella: emotion effects always have the mental trait, and possession explicitly fails if the user or target is immune to mental effects. Conditions themselves don’t carry traits, but most effects that inflict conditions like frightened, confused, or controlled are mental—and often emotion or fear—effects, which is why mindless creatures are typically immune to being frightened or dominated via standard routes.

Some traits, such as mindshift, explicitly let you convert an action into a mental effect, replacing its damage with mental damage and granting it the mental trait while changing any save it requires to a Will save. Immunity to mental means the creature ignores all effects with the mental trait and all mental damage, functionally behaving like a “global mind shield,” whereas the mindless trait is a specific form of mental immunity tied to having only programmed or rudimentary cognition.