Who the hell are you?
The Cataclyst was a magic-based bomb that, when activated, destroyed everything in the current sector of the OASIS; every OASIS avatar, NPC, building, and object would be destroyed and would remain so until the server reset at 12:00 PM OST.
The Cataclyst was used by IOI following their defeat at the hands of the surviving four members of the High Five and over half the population of OASIS. Detonating it, they killed off what remained of their army, Castle Anorak, and half the avatar population of the OASIS. Parzival was revived after the detonation of the Cataclyst with his 1981 quarter artifact
The Cataclyst had been sold in auction and, until the sale of Fyndoro's Tablet of Finding, was the highest selling item in the history of OASIS.
Gunters would sometimes state they had the Cataclyst and threaten to detonate it when they were surrounded by Avatars they didn't like.
When activated, the Cataclyst would destroy every living and non-living thing in the current sector, including the user. Any landscaping, including trees, hills, mountains, and rivers, would be destroyed and replaced with a grassy field until the server reset.