Metalhead

Metalhead is a robot Turtle created by Donatello. He first appeared in the episode Metalhead.

Bio
Metalhead is a turtle-like remotely controlled robot built by Donatello. Donnie salvaged an abandoned Kraang-droid body after a battle and decided to use its highly advanced technology to build an upgraded weapon for himself. The result was Metalhead. He resembles the turtles themselves yet stands about a foot shorter. He has a bandanna built onto his head that is yellow in color and the back of his shell is made from a New York City manhole cover.

History
Metalhead (Episode): Metalhead was first created in this episode. Donnie created Metalhead to fight the Kraang because he thought his bo-staff was not strong enough to use against the Kraang's advanced technology. Donnie brought a Kraang droid body to the sewer and used it's tech to build Metalhead. He later shows the turtles his new creation, and Mikey thinks he is cute and calls him Metalhead. Leo and Raph are less than thrilled by the robot and believe it takes the point from being a ninja. Donnie disagrees and tells them to attack Metalhead to test it out. Raph, Leo, and Mikey all try to best the robotic turtle but Metalhead makes quick work of him. Splinter then tells Donnie that he may take Metalhead out that night for a test run, but to not bring him into combat. Donnie agrees but has no intention of staying out of a fight.

On the mission Metalhead is less than stealthy and Donnie is forced to remain behind as Metalhead's clumsy movements would hinder the turtles mission. However, when Donnie hears the noise of the battle and determines things are going badly, he charges Metalhead into battle. At first, Metalhead completely decimates the Kraang forces, but is eventually damaged so that Donnie loses control. One of the Kraang realizes that Metalhead is derived from Kraang technology and climbs up onto the robot's head. The Kraang takes control of Metalhead and attacks the turtles. Donnie rushes in himself to stop Metalhead and is able to trick the Kraang into knocking a pillar onto itself, destroying Metalhead and defeating the Kraang.

The Pulverizer: Metalhead makes a short cameo in this episode. While the pulverizer is in the turtle's lair, he comes across Metalhead and asks what it is. Donatello then tells him not to touch it.

TCRI- Metalhead appears again. This time he is used to crack the Kraang files.

Booyaka-Showdown: Metalhead was shown in a promo fully functioning.

Abilities and Weapons
Donnie built his robotic reptile to be the most powerful weapon possible. Metalhead bristles with weaponry, from Gatling guns and laser cannons to a baseball bat with a nail in it. Metalhead's arsenal includes a laser cannon embedded in his left fist, while his right fist is rocket powered and can be launched at foes and return to Metalhead's arm. Metalhead also has wings, shoulder-mounted machine guns, and flame throwers. The front of Metalhead's bandanna can open in order launch powerful grenades from his eyes. Even without using any of his special weapons, Metalhead is a powerful fighter. His short, squat frame is impervious to most sharp and blunt force trauma and laser blasts. He was able to catch Leo and Raph's weapons and stop them cold.

As powerful a fighter as Metalhead is, he is actually a very bad ninja. His mechanical body is so heavy and clumsy it is impossible for him to move with any kind of stealth. The simple act of walking causes so much clanking, whirring, and buzzing that it sets off nearby car alarms.