Final boss - The Doom Wiki at

The final boss (often informally called the Icon of Sin because of the Doom II level of which it is a part) is the final boss of Doom II, in MAP30: Icon of Sin.

Cyberdemon - The Doom Wiki at

Icon of Sin (Doom 2016) - The Doom Wiki at

VIOS, Doom Wiki

Demon - The Doom Wiki at

Cyberdemon (Doom 3) - The Doom Wiki at

Mother demon - The Doom Wiki at

Baron of Hell - The Doom Wiki at

Boss, Doom Wiki

Arch-vile - The Doom Wiki at

Marauder - The Doom Wiki at

Doomguy - Wikipedia

Hell guard - The Doom Wiki at

Doom 3: The Lost Mission, Doom Wiki

Spider Mastermind (Doom 2016), Doom Wiki