Fortress of Doom

The Fortress of Doom is a spaceship used by the Doom Slayer as his personal headquarters.

Hub
It is where Doom Slayer travels to missions.

Ripitorium
It is where Doom Slayer practices to rip and tear through Hellspawn with ease. The more demons you encounter, they will be in that very Ripitorium.

Wait, Is That The Unmaker?!
The Unmaker, named "Unmaykr", is found in the Fortress of Doom when you rip and tear through all Slayer Gates.