Polymorph

From NWNWiki

Polymorphing is the changing of a creature's shape through magic. This is accomplished through spells (polymorph self, shapechange) or feats (wild shape, shifter abilities). Polymorphed creatures retain their own minds but have new physical forms, and are unable to use most items, aside from potions. (Equipped items are unavailable while polymorphed, although the feat-based polymorphing does allow some properties from equipped items to be retained in the new form.)

Since creatures do not change types, a slaying or bane weapon designed to kill or harm creatures of a specific type affects those creatures even if they are polymorphed. Likewise, a creature polymorphed into the form of a creature of a different type is not subject to slaying and bane effects directed at that type of creature.

A favored enemy bonus is based on knowing what the foe is, so if a favored enemy polymorphs into another form, the bonus is denied. Similarly, battle training bonuses are based on shape and size, so depend on an opponent's current form. For example, the bonus from battle training vs. giants is lost against a giant polymorphed into something else, but is gained against any creature polymorphed into a giant.