When the player selects the menu option defined by the hook “CanLayOrWhatever”, this hook will be called. This hook can do things such as modifying the character's hit points. It can also cause the character to:
Cast a spell: By setting Hook Parameter[1] to the name of a spell and returning the value “CastSpell”, the engine will proceed as if the player had selected “Cast” followed by the selection of the named spell. Commonly, this will result in the player being offered a chance to select a target of the spell.
Character – The character being viewed
Class – the class of the character being viewed
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