|Fast Facts on Metal Sonic Kai|
Metal Sonic Kai is a gargantuan transformation of Metal Sonic that serves as the final boss of Chaotix. It is also known as Mega Metal Sonic, Emperor Metallix, Project: Chaotix, and Super Metal Sonic (although the Super prefix is generally misleading). No matter its name, which has likely never been made official, it is known for its lack of effort in attacking the player despite its giant, menacing, and powerful appearance.
The battle against it begins with a scene of Metal Sonic collapsing at Robotnik's feet after a prior battle in Newtrogic High Zone. Robotnik uses a device to transform another Chaos Ring into a Dark Ring, and beckons Metal Sonic into the ring. The screen flashes, and the player and partner are dropped into a cyberspace arena (10 rings already in hand) with the new monstrosity looming over them on the right. Despite its new power, it makes no attempt to utilize its size to attack besides an occasional slap with its now-detachable limbs. Eight hits to the shoulder knock one of the offending appendages off of its body. It then hovers behind the arena, using its remaining arm to try to crush the player. The player simply needs to attack the arm after it misses the player to damage it. Eight hits on this arm disposes of it as well. Metal Sonic then moves to the left of the arena, firing off its chest laser. Although Vector might see need to duck, the player can stand under the laser until it finishes firing, then jump at the chest to take down Metal Sonic and finish the game.
Should the player have collected all of the Chaos Rings, a scene shows the rings being destroyed followed by the good ending. Otherwise, the collected rings are destroyed, but the bad ending shows Metal Sonic again in the form from the previous battle hovering menacingly over a burning city, implying that Robotnik managed to obtain a remaining Chaos Ring.
Metal Sonic Kai played a major role (as a much more menacing villain) in the British Sonic The Comic, under the name Emperor Metallix. As the leader of an entire army of Metal Sonics (the Brotherhood of Metallix), Emperor Metallix featured in a number of story arcs, operating out of Robotnik's abandoned base in the Special Zone. Its most audacious plan involved eliminating its former master from the timeline by retroactively preventing the laboratory accident that created Robotnik from Ovi Kintobor.