The Gizoid is an ancient robot, over 4000 years old, built by an ancient civilization that predates even the Echidnas. The Gizoid has an epically destructive power - the power to assimilate any and all actions, attacks, and abilities it sees and use it to full extent. It was first discovered by Prof. Gerald Robotnik, long before the whole Shadow/Black Arms mess, where it assimilated the Ark's technology, went on a berserk rampage, and killed a bunch of people before shutting down and falling in the ocean. Good times. In the fighting game Sonic Battle for the GBA, the Gizoid was later discovered by Eggman (who copied its designs to make the E-121 Phi line) and then eventual by Sonic and pals. Once it was found out that the robot could use Chaos Emeralds to increase it's abilities, Sonic and co. decided to nickname the bot "Emerl". They continued to make an effort to teach Emerl plenty of moves and abilities. In game, this translated into giving the player their own customizable character, whose moves could be taken from any and every other character in the game and mixed and matched to the best of their abilities through an intricate Card System. Emerl would even take on the personalities of the characters he's copied, shouting out phrases they would say and acting in the same manner. Eventually however, he overloaded with power(thanks to Eggman) and went on a berserk rampage, where poor Sonic had to put him down. Emerl still lives on through his successor, G-Mel(who also went on another berserk rampage), whom Tails implanted Emerl's memory into after Sonic Advance 3. While being a GBA handheld exclusive character entirely, Emerl was at least somewhat well recieved by fans, as was Sonic Battle. At least until he goes on another berserk rampage.