The Ultravoid, also sometimes referred to as the Void, is a super-massive, anomalous black hole in space that consumes planets and everything else in its path, and is the main setting of the game Solar Ash. Inside of the Ultravoid, there is a "world" made up of surreal spaces and broken landscapes of different planets that have been consumed over time, with wild gravity, populated with grotesque and violent creatures.
Rei, an agile Voidrunner, travelled into the black hole with the rest of the Voidrunners, in a last ditch effort to save their home world from the ravenous rift in space with the Starseed, however the mission failed and Rei activated the Starseed in an attempt to reverse time, and inadvertently began a time loop. After eventully deactivating the machine and becoming a Remnant, and then being defeated by Echo and merged back with her, the Ultravoid had become inert and stable.
The Ultravoid is shown to bend light around it like black holes in real life does.