Tappet, along with the rest of the NAILs left Cybertron to escape the war. When Cybertron was "reborn" a signal was sent out and the NAILs returned. Upset about the war a riot began against the Autobots and the NAILs. When the Decepticons were used to help with crowd control, where Tappet was attacked by Blitzwing. The riot ended when Optimus Prime announced his decision to leave Cybertron.
When Optimus Prime returned from his absence, Tappet angrily confronted him as "Orion Pax" for the war that lasted over four million years. He was soon went after both Whirl and Sideswipe as well, but Optimus defused the situation.
Tappet does not care for the Autobot government and uses graffiti to express his displeasure. Two Decepticons Needlenose and Horri-Bull, acting as "enforcers" by the Autobots, caught him in the act and started beating Tappet. A group of Autobots soon noticed the two beating up Tappet and diffused the situation. Tappet was arrested for vandalism, but was released on Metalhawk's behalf.
Tappet was later introduced to Sky-Byte, and was among a Cybertronian crowd recruited by Starscream to pressure Prowl into revealing one of his secret discoveries below ground on Cybertron. When they went underground, they found Metrotitan, who declared that Starscream was destined to unite their whole race. In vision he and the other are shown celebrating with Starscream.
Tappet appears to be based on the famous British children's book character Noddy. He has a similar conical blue helmet, red torso, and blue legs. Also his alternate mode is similar to the look of Noddy's car.