Gear Fifth is the fifth and current transformation of Monkey D. Luffy's Gear System. It is a form that allows Luffy to stretch his body to incredible lengths and sizes, and it grants him a variety of new abilities. Gear Fifth was first used by Luffy during his battle against Kaido in the Wano Country arc. Luffy was initially overwhelmed by Kaido's strength, but he was able to transform into Gear Fifth and gain the upper hand. In Gear Fifth, Luffy's body becomes rubbery and elastic to the point where he can stretch it to incredible lengths and sizes. A fanart One Piece progress bar for YouTube with Monkey D. Luffy Gear Fifth.