The act of fusion is where two beings merge together into a whole new identity. There are three principal ways of fusion.
The first is by performing the Fusion Dance, or Metamarian Fusion. This was taught to Goku in the afterlife between the Cell Saga and the start of the Majin Buu Saga. The fusion technique is done by the two beings doing a dance which mirrors the other, and shouting "FU......SION..........HA!" This results in a brand new entity which resembles both fighter (but usually looks more like one than the other). When exectuted correctly the new being is significantly stronger. But there are certain requirements for the fusion:
- The two beings must be very similar in height, weight and build. Also they must have almost identical power levels
- The dance must be done 100% correctly, otherwise bad fusions will occur. E.g: Fat Gogeta occured when Vegeta had his fist clenched
- The fusion will last exactly 30 minutes, and there is no way to separate before that time
- After the fusion there must be a resting time of 1 hour before it can be performed again
Correct Fighters Created: Gotenks and Gogeta
Incorrect Fighters Created: Fat Gogeta, Fat Gotenks, Old Man Gotenks
The next way of fusion is via the Potara Earings. This, unlike with the Fusion Dance, is a permanent fusion. It envolves the two beings placing one of the Potara Earings on opposite ears and the fusion will occur. This results in a brand new entity which resembles both fighter (but usually looks more like one than the other). This apparently is 100 times better than using the fusion dance. But again there are requirements:
- A set of Potara Earings
- The two beings must wear the earings on opposite ears
- Each person can only do it once a lifetime
- The effects are permanent (except inside of Buu, where the laws of physics do not apply)
Fighters Created: Vegetto, Kaiobit
The final way of fusion is Namekian Fusion. This is seen twice in the series. Once when Piccolo merges with Nail, and agin when Piccolo merges with Kami. The fusion is done by one Namek whos body will be used placing his hand on the other who is absorbed into the "host's" body. The fusion is a permanent deal, as Piccolo points out to Goku before the Cell Games. There is no physical alteration to the host Namek, except for a radical increase in power. Also there do not apper to be any requirements except for one Namek knowing the move.
Nameks Merged: Piccolo and Nail, Piccolo and Kami-Sama