Doom The Dark Ages features a lot of strong enemies that both appear as champions, leaders, or normal mobs. Some of the enemies in this game can be extremely annoying to fight, and I am sure many players dread when they catch a sniff of them inside the game. Having finished the campaign myself, I have been a victim of many of these enemies, so it was only prudent to create a list of enemies that made me struggle the most. So that said, here are the hardest enemies to fight in Doom The Dark Ages to save you the trouble:
10. Chaingunner Soldier

Chaingunner Soldier is different from the normal shielded demons, as it also wields a rapid-fire mini-gun that can be extremely annoying around the start of the game. Even though this enemy becomes fodder in late-game content, his shield is hard to break early on, and his mini-gun can be very annoying. So while the Chaingunner Soldier might be one of the most difficult Doom The Dark Ages enemies, he thankfully becomes easier over time.
9. Vagary

The Vagary is a disgusting-looking spider demon with armor on its feet and body. This enemy is very strong and appears as an early game champion (boss). The hardest part of this enemy is shredding its armor, as it takes no damage with it equipped.
The Vagary is also a relatively quick demon, hard to target in the game. It also deals a fair amount of damage, which can feel like a lot early on in the game. So if you want some trouble, then do seek this demonic beauty out.
8. Hell Knight

Hell Knights are one of the most unpredictable enemies in Doom The Dark Ages that appear out of nowhere, jump at you, and deal a ton of damage. This enemy is introduced fairly early in the game but only becomes stronger as the Slayer goes on. In the later chapters, Hell Knights appear with complete suits of armor, making them very hard to kill, especially when you are already fighting other enemies.
In many areas in the game, the developers throw multiple Hell Knights at you in a closed space. The only good part about this enemy is that almost all of its attacks are parryable, so as long as you can parry its attacks, you will win the fight.
7. Nightmare Imp Stalker

Nightmare Imp Stalker is definitely up there on the list when it comes to the hardest Doom The Dark Ages enemies. This is the only enemy in the game that can become nearly invisible, making it very hard to spot while fighting.
Once your attention skips over this enemy, it will appear right behind you and scratch you to death until you find its location and defeat it. Although in terms of damage and survivability, Nightmare Imp Stalkers are not hard to beat. But the sheer annoyingness of fighting this enemy makes up for all that.
6. Cyberdemon

The Cyberdemon is one of the big-boy enemies in Doom The Dark Ages. It features multiple close-range attacks, projectile attacks, and can also shoot you with a minigun. The enemy is very tanky and requires a glory strike to become vulnerable to an execution.
The close-range attacks made by this demon are parryable, but they hit for a ton of damage and are really fast in execution. Overall, this nuisance fits in one of the most challenging enemies to beat in Doom The Dark Ages.
5. Tentacle

When it comes to annoying enemies in Doom The Dark Ages, Tentacle takes the cake with ease. This enemy randomly pops up from the ground in specific areas, utterly unknown to the players, and deals much damage before burrowing underground.
What’s worse is that there are generally multiple Tentacles in one location, and they can destroy your self-worth as a player by taking mere seconds to kill you. The only silver lining about this enemy is that its attacks are parryable, and parrying it instantly kills the enemy. But if you miss out on the parries, prepare to start crying because you will be losing out on your Life Sigils.
4. Revenant

The Revenant is one of the hardest demons in Doom The Dark Ages merely for the fact that it keeps running away. This enemy randomly dashes from one area to another, making it extremely hard to track it with bullets.
Furthermore, it can occasionally become invulnerable while doing a specific attack. Thankfully, parrying this attack can stun the Revenant for a couple of seconds, making it easier to shoot at it. Also, you can throw the Shield Saw at it to stun it into one place for a quicker execution.
3. Acolyte

Much like the Revenant, the Acolytes also move around extremely fast, with the key difference being that they teleport instead of dashing. These enemies only start appearing in late-game chapters and can be very annoying to defeat in groups.
Much like the Revenant, the Acolyte can also create a shield that makes it immune to damage. When this happens, you can only wait for the shield to disappear before you can target it again.
2. Agaddon Hunter

Coming in as the runner-up, the Agaddon Hunter is one of the strongest and most balanced enemies in Doom The Dark Ages. It features quick melee attacks, strong ranged attacks, and can sustain much damage.
Some of the variants of Agaddon Hunter can randomly create shields, becoming immune to damage for some time. This enemy also deals a lot of damage with its attacks and would have taken the number one spot in this list if only Cosmic Baron weren’t the representation of the most aggressive enemy in the game.
1. Cosmic Baron

The Cosmic Baron is a big, strong demon that appears out of nowhere, closes in on the player quickly, and attacks with a non-stop combo. This enemy is very much like a bigger and meaner version of the Hell Knight, and can often jump scare by getting close out of nowhere and start throwing you around.
The Cosmic Baron hits like a truck with each attack, which is why it is fortunate that you can parry its attacks constantly. Sadly, his attacks have a very tight parry window, even for those that play on the ‘Hurt Me Plenty’ difficulty. As such, its aggressive nature makes it the hardest enemy in Doom: The Dark Ages.
And now you know about the hardest enemies in Doom The Dark Ages. If there are other enemies that give you more trouble, tell us about them in the comments below.