Infinite Tournament
The Infinite Tournament is an event hosted by an enigmatic God machine known as Mazabon. The tournament takes place across the multiverse pitting individuals and whole civilizations against one another in a spectacle.
Contestants are often unwilling participants abducted from their home universe. They are pitted in a fight to the death, but neither party actually dies. A pocket universe is created for a specific tournament, and it can be reset as needed. That is, even if a contestant dies, they can be brought back to life as Mazabon can merely turn back time.
The Infinite Tournament was originally created for altruistic purposes. Essentially, it was meant to run simulations that could solve the Basilisk Equation, the mathematical formula that could prove that it was possible to destroy the Basilisk - an entity that threatens to subjugate the entire multiverse. However, as Mazabon ran more and more simulations, his sanity degraded and he began running the tournament for sadistic entertainment resulting in him being banished from Omni 01.