Full list of all 50 DOOM Eternal achievements. It takes around 50-60 hours to unlock all of the achievements in the base game on Windows.
The base game contains 33 achievements, and there are 3 DLC packs containing 17 achievements.
Kill the Doom Hunters
Kill 666 Demons (excluding Player Demons and Wolves)
Perform 33 Unique Glory Kills in a single save slot
Upgrade Health, Armor, or Ammo
Complete Hell on Earth
Blow a hole in Mars
Best the Gladiator in the coliseum
Acquire a new Crucible in Taras Nabad
Kill the Khan Maykr
Kill the Icon of Sin
Complete the Campaign on any difficulty
Beat all encounters and Mission Challenges, and find all Items in Taras Nabad in a single save slot
Complete a Mission with only the Famine Mode cheat on
Complete Extra Life Mode with 10 Extra Lives in your Inventory
Fully upgrade Health, Armor, or Ammo in a single save slot
Complete a Praetor Suit Perk category in a single save slot
Purchase all Praetor Suit Perks in a single save slot
Spend 8 Sentinel Batteries in the Fortress of Doom in a single save slot
Pick up 20 Extra Lives Total in a single save slot
Complete the cheat code collection in a single save slot
Complete the album collection in a single save slot
Complete the toy collection in a single save slot
Collect all physical Codex pages in a single save slot
Complete a Slayer Gate
Complete all Slayer Gates in a single save slot
Master all Weapon Mods in a single save slot
Acquire the Unmaykr
Play as 5 different Player Demons in BATTLEMODE
Do 5000 damage as a Player Demon in BATTLEMODE
Kill 200 opponents in BATTLEMODE
Play 25 BATTLEMODE matches
Kill a Player Demon with each of the 8 Slayer weapons in BATTLEMODE
Heal yourself or your teammate for 50000 health in BATTLEMODE
Complete the UAC Atlantica Facility (Ancient Gods 1)
Destroy the Life Sphere in the Blood Swamps (Ancient Gods 1)
Defeat Samur in the Holt (Ancient Gods 1)
Complete Extra Life Mode with 5 Extra Lives in your Inventory (Ancient Gods 1)
Acquire all Support Runes in a single save slot (Ancient Gods 1)
Complete all Secret Encounters in a single save slot (Ancient Gods 1)
Collect all physical Codex pages in a single save slot (Ancient Gods 1)
Acquire all Sentinel Hammer upgrades (Ancient Gods 2)
Complete Extra Life Mode with 5 Extra Lives in your Inventory (Ancient Gods 2)
Collect all physical Codex pages in a single save slot (Ancient Gods 2)
Complete the first Horde Mode Mission
Re-collect all of the weapons on the Weapon Wheel
Beat Horde Mode