Combat Action: Cast a Spell

An arcanely-gifted PC can cast a spell as a Main Action. If they’ve suffered any hit point damage this round, drawn or sheathed an item with their spellcasting hand, or have been severely jostled they cannot take this action.

If they suffer hit point damage while casting, such as by someone who has held their action to attack at that moment, the spell fizzles uselessly and the spell slot is wasted.