Tyranus was once a barren, volcanic planet that was inhabited by monsters and the undead because of the surface of the landscape. Sometimes, blacksmiths from across the Multiverse tend to use it's lava source as fuel for their furnaces.
After escaping execution and slaughtering many people at the Interdimensional Criminal Asylum, Enoch and his Grand Empire traveled to the dreadful Tyranus and used it now as his homeworld and built his castle as his base of operations.
Tyranus is first seen in Legotropolis' Most Wanted, there, Enoch declares war on the heroes and orders the Grand Empire to find the Foundation Elements.
In Fate of the Multiverse, it became a major battlefield for the final showdown. After Enoch's death, the world was destroyed by the Power Stone and therefore never seen again.