Doom Eternal Walkthrough — Start to Endgame

Doom Eternal is the most aggressive FPS ever designed. The combat loop forces constant movement and resource management: chainsaw fodder enemies for ammo, glory kill staggered enemies for health, flame belch for armor pickups. Standing still means death. The weapon switching system rewards rapid swapping between the Super Shotgun and Ballista for maximum DPS, creating a rhythm-action feel to combat encounters. Every demon has a specific counter-strategy and exploitable weak point. The Slayer Gates offer optional ultra-hard encounters, and the two DLC campaigns (Ancient Gods 1 & 2) are considered even better than the base game.

This walkthrough takes you from your first session to endgame content. Each phase has specific goals, priorities, and milestones. Follow this path to avoid common traps that stall most players.

Quick Progression Summary

Phase 1: Getting Started — Hell on Earth

The opening level set in a demon-invaded city. Teaches glory kills, chainsaw mechanics, and basic weapon switching. The level introduces combat flow in a relatively forgiving environment. Contains the first Slayer Gate.

Level/Difficulty: Mission 1 Key Rewards: Core mechanic tutorials, first Slayer Gate, weapon mods

What to Do in Hell on Earth

1. Learn glory kills. Staggered enemies (flashing blue/orange) can be glory killed with a melee finisher that drops health pickups. Spend your first session getting comfortable with this.
2. Pick Ballista Swapper as your starting role. It's the most forgiving option.
3. The resource loop is: Chainsaw for AMMO, Glory Kill for HEALTH, Flame Belch for ARMOR. Never neglect any of the three — they keep you alive. Memorize this triangle.
4. Acquire your first weapons upgrade — Ballista or whatever's available.
5. Clear all main content before moving on.

Phase 1 Checklist

• Understand glory kills fundamentals
• Ballista Swapper selected and functional
• Hell on Earth main content cleared
• Ready for Exultia

Phase 2: Early Game — Exultia

A Sentinel fortress level that introduces platforming and the dash mechanic. Exultia's arenas teach aerial combat against Cacodemons and the importance of vertical movement. The Celestial Locator is found here.

Level/Difficulty: Mission 2 Key Rewards: Dash mechanic, aerial combat, Celestial Locator, Sentinel Battery

What to Do in Exultia

1. Work on chainsaw ammo. The chainsaw instantly kills fodder demons (Imps, Soldiers, Gargoyles) and drops a shower of ammunition. This system becomes critical from here on.
2. Farm for Ballista if you haven't already. It's the key upgrade for this phase.
3. Quick-swap SSG→Ballista is the highest DPS combo. Fire SSG, immediately swap to Ballista, fire, swap back — the swap animation cancels both weapons' recovery.
4. Complete all objectives before pushing to Doom Hunter Base.
5. Consider whether Super Shotgun Main might suit your playstyle better than Ballista Swapper.

Phase 2 Checklist

• chainsaw ammo integrated into gameplay
• Ballista acquired
• Exultia fully cleared
• Ready for Doom Hunter Base

Phase 3: Mid Game — Doom Hunter Base

Features the Doom Hunter boss — a hovering demon with a shield phase and a vulnerable second phase. The Doom Hunter teaches target-specific weapon strategies (Plasma Rifle for shields, SSG for flesh). Three Doom Hunters must be defeated.

Level/Difficulty: Mission 4 Key Rewards: Doom Hunter boss experience, Plasma Rifle shield-breaking mastery

What to Do in Doom Hunter Base

1. Master weapon switching. Doom Eternal is designed around rapid weapon switching, not reloading. This unlocks a new layer of gameplay.
2. Start working toward Super Shotgun. It's the best weapon and becomes accessible around now.
3. Weak points disable enemy attacks permanently. Shoot the Arachnotron's turret, the Revenant's shoulder launchers, the Mancubus' arm cannons. This dramatically reduces incoming damage.
4. This area is the main skill check. If you can clear it, you're ready for late game.
5. Start investing in dash mechanic for the tactical depth you'll need going forward.

Phase 3 Checklist

• weapon switching mastered
• Super Shotgun acquired or in progress
• Doom Hunter Base fully cleared
• Ready for Mars Core

Phase 4: Late Game — Mars Core

The iconic BFG-10000 level where you fire yourself from a giant cannon INTO Mars. The level culminates in the most intense arena fights in the base game. Mars Core demands mastery of all weapons and movement systems.

Level/Difficulty: Mission 9 Key Rewards: BFG-10000 sequence, intense arena combat, story progression

What to Do in Mars Core

1. Finalize your build. You should be running Super Shotgun Main or Ballista Swapper with optimized gear.
2. Super Shotgun should be your primary. If you don't have it yet, prioritize getting it.
3. Dash has two charges — never use both at once. Always save one charge for emergency dodging. The second charge regenerates in 3 seconds.
4. Slayer Gates optimization starts here. Small improvements compound into massive advantages.
5. Farm this area for the resources needed to push into Final Sin.

Phase 4 Checklist

• Build fully optimized
• Super Shotgun upgraded to max
• Mars Core fully cleared
• Ready for Final Sin

Phase 5: Endgame — Final Sin

The final level featuring the Icon of Sin boss fight — a massive demon destroying a city. The two-phase fight requires breaking armor pieces then targeting flesh. The arena constantly spawns additional demons, forcing resource management while damaging the boss.

Level/Difficulty: Final Mission Key Rewards: Icon of Sin boss fight, game completion, Nightmare difficulty unlock

What to Do in Final Sin

1. Final Sin tests everything. Come prepared with your best build and gear.
2. The Marauder is the most technical enemy: only vulnerable during his green-eye flash (when he prepares to melee). SSG→Ballista swap during the flash window is the standard counter.
3. The endgame loop: run Final Sin, optimize gear, push harder content.
4. Experiment with Micro Missiles for a fresh take once you've mastered the standard builds.
5. This is where Slayer Gates mastery separates good players from great ones.

Phase 5 Checklist

• Endgame content on farm
• Best-in-slot gear acquired
• Final Sin fully cleared
• Ready for challenge content

Common Progression Mistakes

• Standing still and trying to aim precisely — Doom Eternal punishes stationary players with overwhelming damage. Keep moving constantly, shoot while moving.
• Ignoring the chainsaw — running out of ammo is entirely preventable. The chainsaw regenerates one fuel pip automatically. Use it on fodder enemies every 30 seconds.
• Not using Flame Belch for armor — many players forget Flame Belch exists. Burning enemies drop armor on hit and on death. Use it before glory kills for maximum armor recovery.
• Fighting the Marauder with ranged weapons — he blocks everything except during his brief green-eye attack window. Bait his melee, then quick-swap combo during the flash.
• Saving BFG ammo for 'later' — BFG ammo pickups appear in fixed locations. Using BFG when overwhelmed, then picking up ammo later, is more efficient than hoarding.

Key Tips for Smooth Progression

1. The resource loop is: Chainsaw for AMMO, Glory Kill for HEALTH, Flame Belch for ARMOR. Never neglect any of the three — they keep you alive. Memorize this triangle.
2. Quick-swap SSG→Ballista is the highest DPS combo. Fire SSG, immediately swap to Ballista, fire, swap back — the swap animation cancels both weapons' recovery.
3. Weak points disable enemy attacks permanently. Shoot the Arachnotron's turret, the Revenant's shoulder launchers, the Mancubus' arm cannons. This dramatically reduces incoming damage.
4. Dash has two charges — never use both at once. Always save one charge for emergency dodging. The second charge regenerates in 3 seconds.
5. The Marauder is the most technical enemy: only vulnerable during his green-eye flash (when he prepares to melee). SSG→Ballista swap during the flash window is the standard counter.

For detailed build optimization, see Doom Eternal builds. For quick wins, check tips & tricks.