Hytale modders have gotten Doom running in the game before it's even out.

According to modder Tr7zw, getting a version of Vanilla Mocha Doom running in Hytale before it’s even out took two or three relatively sleepless nights of work. For that sacrifice, their character can stand in the sky above the landscape and Doom away on a monitor made of blocks.

Video: Playable Doom in Hytale - Duration: 2 min