Doomdesire.exe (often referred to as "Doom") was the final boss of Mirror World Rescue. He is often portrayed as a blob of dark black static with a single eye in the center, with green sparks around his body. His body has the unique trait of being able to change shape at will, and he can also manifest parts of himself to clone opponents and turn these clones against the originals. His weakness is horribly easy to exploit - fire. In the original MWR, Doom could not be harmed by any type of attack except for Fire-elemental attacks.
Doom's name originates from Jirachi's signiture move in Pokemon "Doom Desire", a Steel-type move that has the same effect as Future Sight, however, is much more powerful.
The Virus- Doomdesire is apparently responsible for the strange disease in the Mirror World.
Kill It With Fire- How you fight Doom.
Demonic Possession- Especially to Tharuk.
Frickin Laser Beams- He shoots these.
The Blob- While looking like this.
Obviously Evil- Like most Kirby bosses. He's a giant black evil blob that spreads virus and bad stuff.