Extra Cast (MPリーヴ MP Rīvu , lit. "MP Leave") is an ability that appears in Kingdom Hearts III. It allows the user to use one more magic cast before running out of MP.
In Kingdom Hearts III, Extra Cast is a support ability that costs 3 AP to equip. When having more than 1 MP and using a magic spell or ability that would empty the MP gauge, it will reduce the user's MP to 1 instead of fully depleting it. Cure Magic and Links still fully deplete the MP gauge.