Commando/Doom 3

"Die, Mortal!"

- A Chaingun Commando in hot pursuit of the player

The Commando is the final class of former humans in Doom 3 the player will encounter, loosely inspired by their classic iteration.

While their Z-Sec counterparts were originally Mars-Sec personnel, Commandos were formerly Marines who have been transformed into demonic supersoldiers. They wear a futuristic German Stahlhelme-like helmet with a pair of camouflage army pants and glowing robotic eyes.

Commandos are surprisingly unique from other Zombies, as they are technically demons rather than demonically-possessed human beings. A brief cutscene depicts Dr. Betruger casting a spell on a Marine, who slowly transforms into a Commando as Betruger continues his incantation. This can suggest that Commandos were former humans like the Zombies, but underwent a more complex means of demonic transformation, rather than a simple demonic possession.

Commandos first make their appearance in the Monorail level and in the Delta Labs. Aside from their high offensive capabilities, Commandos are also very intelligent as they appear to retain their own human language, often shouting words like: "You!" or "Die!" upon spotting the player. Relying on both their superhuman strength and skill in combat, they are among the most elite of the campaign's monsters, posing a similar threat level as the Revenant, and exceeded only by the likes of the Arch-vile, Mancubus, and Hell Knight.

Combat characteristics
There are two types of Commando: the first type does not carry a firearm but has its right arm demonically modified into a muscular, whip-like tentacle; the second type has both its human arms intact and carries a Chain Gun. Interestingly, the Tentacle Commando stands a full head taller than a normal human, while the Chaingun Commando is the same size as a normal human soldier. This could most likely be based on the game mechanics as the player is able to avoid a Tentacle Commando's strike by crouching during its attack.

Commandos typically appear individually or in small groups of two or three, although they often appear alongside other enemies such as Z-Sec soldiers or Imps. Upon death, a Commando's body will burn up like those of other demons.

Tentacle Commando
This monster runs at lightning speed and can sprint a lot quicker than the player, making it the fastest enemy in the game. It will quickly close in to lash out its tentacle arm, using it as a sort of whip. Occasionally, it will perform a short range leap attack with its knee which is nearly impossible to dodge. When it gets close enough not to rely solely on his tentacle "whip", it will attack the player with a rapid series of punches and kicks, causing the player to be thrown back from several feet, although there is a lag duration for them to initiate this. Being exceptionally intelligent monsters, Tentacle Commandos can rely on tactics not seen from other enemies, such as leaping down from overhead balconies or platforms while using their tentacles as grappling ropes, or even using security overrides to unlock locked doors.

Chaingun Commando
Arguably the most dangerous of the game's mid-level demons, this Commando is more accurate than a Machinegunner Z-Sec. It carries a Chain Gun, and will engage in continuous fire in a single prolonged burst, before it momentarily pauses, immediately taking cover by sidestepping to a corner. Often times, if it notices the player retreating while it is firing, it will stop to chase after the player and re-engage fire once the player is in its line of sight. Like the Z-Secs, they will also crouch while firing to present themselves as smaller targets. While it does not rely on melee combat like it's Tentacle brethren, it still maintains enough mobility to quickly close in on the player. Drops a Chain Gun when killed.

Tactical analysis
In general, both types of Commandos are considerably tougher than their classic counterparts, with the Chaingun Commando being capable of surviving a direct rocket hit and the Tentacle Commando possessing high mobility to outrun the player. Players are expected to take these types of enemies very seriously by relying on sufficient tactics to take them down.

Tentacle Commando
Unlike most other monsters in the game, which can allow struggling players to retreat by outrunning them, the only recommended strategy to desperately deal with a Tentacle Commando is to immediately kill it through whatever means necessary once they spot you. As they can move a lot quicker than the player, there is no opportunity given for a safe retreat.

The Chaingun or Plasma Gun are the most efficient weapons to take them out at range. The Machine Gun can also work well, but since it does less damage than the other two weapons, it will give the Commando more opportunity to move in towards you to strike.

Given that it moves at very high speed, it is inevitable to occasionally engage in close combat against these brutes. The Chainsaw is the most effective weapon in close range, although two point-blank Shotgun blasts (or one on the head) can also take it out instantly. Regardless of whatever weapon you use, it is necessary to immediately crouch once the Commando closes in and performs a leap attack, as you can avoid the hassle of suffering damage by its tentacle attack in this manner.

If worst case, if you dodge their whip attack and the Commando still survives from your counterattack, keep firing away until it falls, as it will resort to kicking and striking the player non-stop. Since there is a slight lag duration, this will give you more than enough opportunity to land a finishing blow before it initiates its second attack.

The Lost Mission and Resurrection of Evil features the double-barreled shotgun, which works wonders than the standard Shotgun, as one blast at point blank range can instantly kill a Tentacle Commando.

If your aim is reliable and you can maintain your timing very well, you can also use the Rocket Launcher and Grenades to instantly kill them before it closes in on you. Be very cautious, however, not to caught in the explosions of these weapons and otherwise hurting yourself.

Chaingun Commando
In general, the best way to take out this Commando is from long range as their accuracy is somewhat reduced from a distance. The Rocket Launcher is probably the best weapon for the player to use. It take two rockets to bring them down, although one rocket to the head will immediately neutralize them.

When fighting at long range, try to maintain cover as occasionally as you can, as the Chaingun Commando will engage in continuous fire, which will damage you overtime. While it is taking cover in a corner, it will occasionally have its head briefly exposed. You can take this opportunity to aim for the exposed head to do damage to it.

Under extreme circumstances should players be forced to fight the Chaingun Commando at close range, the Chaingun and Plasma Gun can work well. The Shotgun, while effective, is probably not the best bet as it takes 2-3 blasts to take them out. Be very quick, however, to take out this Commando from close range, as continuous fire from its Chaingun up close can build up massive damage overtime.

You can also feign retreat to lure it into a corner where it last saw you, in which case, you can use the Rocket Launcher or a Grenade to finally take them out once it reaches its position where you previously were. Just be careful not to end up trapping yourself in this process if it still survives.

Trivia

 * The Chaingun Commando is similar to the Zombie Soldier from Serious Sam 2 in that they are both zombies that wield miniguns (chainguns in the Commando's case) and wear German World War II-styled helmets. They may also be a homage to id Software's Wolfenstein series.
 * The Commandos in the Alpha version of Doom 3 had slightly different voices; their voices sound more robotic and spoke more frequently, as they can be heard shouting taunting phrases like "You will not escape!" or "I smell fear!" (the latter quote eventually spoken by Sergeant Kelly in the final game).
 * In the cutscene where a marine was converted by Betruger, he was not wearing a helmet. However after the conversion, he mysteriously wore one.