Cyberdemon/Doom 3

The Cyberdemon is the final boss and most powerful monster of Doom 3. It stands roughly 20 feet tall, more than 3 times as tall as a human soldier. Like its original counterpart, the Cyberdemon attacks by firing a salvo of 3 consecutive rockets from its arm-mounted rocket launcher. Unlike the original version, it can also step on the player, killing them instantly.

Unlike its original counterpart, it cannot be hurt with conventional firepower; instead, the player has to utilize the most powerful weapon in Doom 3, the Soul Cube, to kill it. The Soul Cube states that only it can kill "Hell's mightiest warrior" presumably referring to the Cyberdemon. It takes 4 shots from the Soul Cube to kill the Cyberdemon. Fortunately, there are plenty of lesser demons on the level that can be killed to charge the Soul Cube.

Many players complained about the fact that the Cyberdemon is no longer vulnerable to the other weapons, and thus, a mod was released just some weeks after the release of Doom 3 that made the new Cyberdemon vulnerable to conventional weapons again.

Some differences of this new incarnation of the monster compared to its classic counterpart can be seen on the picture to the right. Though it is not shown in the picture, this incarnation has a long tail, extending from the machinery on its back. Another noticeable difference is that the rocket-launcher is now located on the right arm instead of the left.

The Cyberdemon did not make an appearance in the expansion pack Resurrection of Evil, so the one that was killed at the end of Doom 3 was supposedly the only one.

The Cyberdemon is also the only monster from the original games to be a boss.