Fast is a special status effect that appears in Paper Mario: The Thousand-Year Door.
Fast is a positive status effect that allows the user to attack or act twice in one turn. This status is very useful especially for tough boss fights. Mario can only get the Fast status by having Goombella use her special move, Rally Wink, on him (however, it will only last for one turn). Macho Grubba is most famous for using the Fast status as he always uses it in battle whenever it wears off (he uses it as soon the fight with him starts as well). Beldam of the Shadow Sirens can cast Fast on herself as well usually following it up with a negative status effect onto Mario or his partners.