Zepp is a floating continent composed of several islands which can be accessed through the use of airships and elevators. It's size and location is unknown. Unlike other stages, Zepp is heavily urbanized and mechanized.
Zepp has shown a degree of political autonomy as it had taken the stand to preserve Black Tech which the UN had already prohibited because of environmental damages. However, Zepp appears to have tolerated slavery as Potemkin was one. Slaves in Zepp were treated with strength enhancing steroids and bounded by a special limiter. In 2180, a revolution led by Gabriel toppled the government and freed the slaves. Because of this, Gabriel held power as president with Potemkin as his loyal guard. In 2182, President Erica Bartholomew of A Country formed an alliance with Zepp to break from the control of the Assassin's Guild. The most recent involvement of Zepp in the storyline is in Sin's short story where Sol Badguy travels to the place for bounty hunting business.
In Accent Core, a P.W.A.B headquarters is located in Zepp, causing several characters like A.B.A and Baiken to travel to it. It is also implied that Robo-Ky's are manufactured in Zepp as it is the robots' stage.
In the alternate timeline, the airship fleet of Zepp let by Potemkin fights with Commander Sol Badguy, implying that Zepp fights along the Holy Knights during the Crusades.
- "Zepp" is likely to be a reference to the 60s–70s English rock band Led Zeppelin.