Kuraimaru

Kuraimaru is Gohan's Clone.

Backstory
After Cell was defeated,a small robot fly(possibly one from the Red Ribbon army)it gather data from Gohan and Cell's Battle.After returning to it's base,it relayed the data to it's creator.The doctor who made the fly(Dr.X) Created a clone in Gohan's image and with his all his powers,A year later the clone,broke free.He knew what he was,but he wants to kill Gohan, believing it his fault he is a clone.

Personally
Kuraimaru is a dark, cruel,cold, callous, dispassionate figure.Kuraimaru has absolutely zero remorse over his actions and can kill with out thinking twice.He also refers to him self with the suffix Sama (meaning lord or master)He shows no respect for living creates and believes all life is expendable.

Power
He has all for Gohan's powers(except Super Sayian and Dragon Buster)and some of his own,such as the ability to turn into a black mist,move thought shadows,summons shadow creates and weapons(mainly swords)rabid healing factor,and the ability to in evade others dreams.He has also created a new version of Kamehameha(Ankamehameha) and Genki Dama(Angenki Dama)