Axiom Nexus is a large metropolis located somewhere within the BZPB Multiverse. It was so vast that, when Blackout and Ynot arrived on its fringes, Blackout believed that it would take them two weeks to reach its centre on foot. Despite its size, its only inhabitants were its ruler, Zeta, and his enforcers, Dirge and Thrust. It was left completely empty when Zeta was defeated and exiled.
The Reign of Zeta
Zeta ruled Axiom Nexus as its sole inhabitant until the Decepticon brothers Dirge and Thrust appeared in the city. Zeta employed them as his personal enforcers and had them help him protect Axiom Nexus from intruders.
During the Battle for the Frozen Throne, Blackout and Ynot were sent into interdimensional space and Ynot broke the fourth wall, which created a hole in the fabric of the multiverse that sucked them both in and transported them to the edge of Axiom Nexus. Zeta soon located Blackout and attacked him, but fled when he noticed that Ynot was also there. Blackout surmised that he and Ynot would have to battle Zeta to force him to let them leave Axiom Nexus. The two Makuta decided to head to the Axiom Nexus Central Tower to confront Zeta despite the fact that Blackout believed that it would take them two weeks to reach the centre of the metropolis on foot.
Meanwhile, Zeta sent Dirge and Thrust to kill Blackout and Ynot. Thrust fired a missile at Blackout, but was blown up by Ynot in retaliation. Ynot then proceeded to teleport himself inside Dirge, which caused most of Dirge's body to explode (minus his head, which remained active and conscious). Before Blackout and Ynot could proceed, however, Archer appeared in front of them and gave them gifts from Zev Raregroove. Golden Flame then appeared and set Archer and Blackout on fire for some reason, which resulted in Golden Flame being beaten up and sent to a hospital somewhere.
Zeta then flew towards them and blasted Archer, but crashed into the ground when Archer slashed at him and retreated once more. However, Ynot found Zeta and defeated, humiliated, and exiled him from Axiom Nexus. Axiom Nexus was then completely uninhabited save for Dirge, who remained unable to move and had only his thoughts for company for the next 50 millennia.
In 150,082 CMT, Zeta appeared in Chocoman's base and forced Kakamu to reveal where Ynot was so that Zeta could get revenge on Ynot for exiling him from Axiom Nexus. Zeta then travelled to Ynot's location via portal and tried to fight him, but Ynot had forgotten Zeta in the 50 millennia that had passed since their last encounter, so he simply dropped the crazed robot through a portal to Aeon instead of fighting him.
Later that year, a Platinum Lantern Ring travelled to Axiom Nexus and selected Dirge as its bearer. The Architect and User MY followed it to Axiom Nexus and persuaded Dirge to join the Platinum Lantern Corps.
In Zeta's second attempt to get revenge on Ynot, his mention of Axiom Nexus jogged Ynot's memory and caused him to remember his visit to the city 50 millennia ago. Ynot decided to send Zeta back to Axiom Nexus himself, so he drew Ka-Oni-Santsu and slammed it into Zeta with enough force to send him into hyperspace and through the fourth wall, which was close to how Ynot had ended up in Axiom Nexus in the first place.