Berserko (aka Drakus) was a minor villain, appearing in only one episode of the classic 1987 TMNT series. It's revealed that he is Krang's weapons engineer who helped him design the Technodrome. However, once it was finished, Krang blasted Berserko out of Dimension X, and destroyed his home world.
He returned, centuries later, with a new mission: Revenge.
Berserko is as tough as he looks. He posses incredibly unmatched fire power, as well as other highly advanced alien weaponry. He is also very intelligent, and a master weapons designer. Not only did he help create the Technodrome, he also built an entire army of deadly robots he calls, "Cyber Drones". And, he built a super tank which he names, "The Annihilator", which according to him, has TWENTY times the Technodrome's power! Unfortunately Berserko's annihilator is experiencing a malfunction. Berserko threatens to fry Krang unless he tells him how to fix it. Krang reluctantly agrees. After successfully defeating Berserko, the Ninja Turtles escape with the new villain in tow as the Annihilator plunges into the river and explodes upon impact.
Berserko is also the main villain in the handheld game Teenage Mutant Ninja Turtles: Dimension X Assault. He has a plan to destroy the Earth as revenge on the Ninja Turtles. He utilizes "Gamma Bombs", which must be deactivated at the end of every level (save for the final stage), and finally appears in his "Annihilater" vehicle as the final boss.