The villains were all united by Terrorax and each of them have different origins, despite they all share something in common: they are assassins.
When Lord Nexus said to Terrorax that he had understimated Max Steel and his team, he shows a trio of assassins in stasis and gives a brief descritpion about their origins. Terrorax charges them with his Terror Energy, and wakes them from their stasis.
Each of them is sent to a specific location to fight Max and his team. Snare fights against La Fiera, Night Howl against Max Steel and Monstro against C.Y.T.R.O. and Tempestra. They are eventually defeated and are misleaded to be dead, but as soon Max's team left, they quickly recover to another battle.
When Max's team arrived on Terrorax's secret hideout, the villain sents Team Terror to take on Team Turbo. La Fiera fights against his evil counterpart, Night Howl, with his brand new Turbo Raptor Mode, while Max uses his Turbo Sword to slash Monstro's minions and Snare fights Tempestra with his deadly weapons. Eventually, Night Howl is tossed in the wall and faints, Monstro is slashed in half by Max and Snare is hit by his own saw in the shoulder by Tempestra.
After Terrorax is successfully defeated, Max and his team escapes from the villain's hideout and each of them carry a member of Team Terror. Terrorax, however, is left to perish. They are lastly mentioned by a Nexus agent stating that their new agents were captured.
Terrorax freeds Team Terror from Team Turbo's prison and goes to a room where his Terror Energy Generator was. Terrorax commands his minions to steal it and after they doing so, he leaves a bomb, which explodes alongside with various others shortly after the group left the base. They go to the Pantheon, where Team Terror and the Elementors are charged with an enhanced Terror Energy.
When Max and his team were heading to the Pantheon, Team Terror suddenly attacks them. To fight against them, Max's friends transform into their new Turbo Modes and goes face-to-face against their evil counterparts. Due to their enhanced Terror Energy, Team Turbo is mercilessly defeated by the villains. C.Y.T.R.O. and Rayne are captured, while Alex is stuck on a bionic panther form thanks to a bite from Night Howl.
Later on, Max invades the Pantheon alongside with Alex and each member of Team Terror are individually taken down. Monstro is tossed on the sea (possibly dying from drowning), Snare is reduced to pieces by Alex on his bionic panther form, and Night Howl dies by carbonization. Their leader, Terrorax, burns to ashes during a confrontation with Max Steel.
- Alongside with Plaztek, they were one of the few villains that were killed by Max Steel rather than contained.