Gotenks

Gotenks is one of the briefly playable characters in Dragon Ball Z: Kakarot.

Majin Buu Saga
When Goten and Trunks perform the fusion dance, they become the mighty Gotenks! Though powerful, he's extremely cocky and mischievous, which often causes problems in fights This type of fusion only lasts for thirty minutes, after which the two turn to normal. The fusion process is difficult to learn and even harder to master. as the two warriors must match each other perfectly in Ki and in movement. One small mistake is all it takes to produce an emaciated or obese warrior.The fusion dance is a technique developed by the Metamorans and the signature vest and pants a fused warrior wears is the traditional dress of that alien race. Originally instructed to perform the fusion dance as Super Saiyans in order to produce the strongest warrior possible. Goten and Trunks were able to transform after fusing. They most likely did so to make their power-up to Super Saiyan that much more dramatic. Despite being just a child, Gotenks is able to achieve the Super Sayian 3 transformation, a feat managed previously only by Goku. This form boasts power that surpasses even Buu, but can only be maintained for five minutes after which fused warriors must wait an hour before fusing again.