| Beginning | End |
|---|---|
| Second Age, 20 years before the Third Age | Third Age |
| Place | |
| Infernus | |
| Outcome | |
| Avernic demons overthrow Chthonian demons. Cthonians are either slain or cast to the Abyss. Zamorak achieves full godhood. | |
| Combatants | |
| Avernic demons | Cthonian demons |
| Commanders | |
| Zamorak | Unknown |
| Casualties | |
| Many Avernic demons | Many Cthonian demons |
| Concurrent war | |
| Gielinorian God Wars | |
For many years, following the arrival of Zaros and the pact made between him and Hostilius, the demon armies served Zaros in his wars on Gielinor.
However, the Avernics stationed in Gielinor began to harbour rebellious thoughts against their Chthonian leaders, who resided in distant luxury. Zamorak used this dissatisfaction to sway the Avernics to his side, including two Tsutsaroth who were willing to pledge their allegiance to him. In time, Zamorak would use many Avernic in his rebellion against Zaros. Amongst them were the Tsutsaroth Thammaron and Zebub.
With Zamorak's victory over Zaros, the surviving demons opened a portal and took Zamorak with them to Infernus to fulfill his part of the bargain.
For nearly twenty years, Zamorak used his powers and led the Avernics to eventual victory over the Chthonian demons, with most of them being slain, or cast into the Abyss.
With the rebellion complete, Zamorak and his demonic army returned to Gielinor.