Praxus is one of Cybertron's city-states, located in the northern hemisphere.
Praxus was a progressive state, its Helix Gardens a symbol of the Golden Age, and its Assembly was where scientists of Crystal City and Nova Cronum presented their findings. Many of its citizens approved of Megatron's anti-caste system beliefs, but were disappointed by his militant direction. Megatron felt betrayed by this reaction, and so he sent Seekers, Constructicons, and Bruticus Maximus to attack. The Praxians threw in their support with the Autobots. With Praxus far from primary Decepticon territory, Megatron ran into the same supply problems as the Autobots normally did, and Praxus became the war's first stalemate. With thousands dead and the city ruined, Megatron conceded defeat and his soldiers left.