“WoW Forever Ulduar 25-Man Raid Guide (2026)”

✦ Editorial

Ulduar is the second 25-man raid of WotLK 3.3.5a and the most-mechanically-complex raid in the expansion. The 14-boss progression from Flame Leviathan to Yogg-Saron is the standard "hard mode" raid in 2026, and the 11 optional hard mode bosses reward some of the best gear in the game. Plus the secret Algalon fight is one of the most prestigious encounters in WoW history.

This guide is for WoW Forever players in 2026 who are stepping into Ulduar 25 for the first time. By the end, you'll know the boss order, the hard mode mechanics, the optional Algalon fight, and the path to Mimiron's Head.

Quick answer up front: Ulduar 25 on WoW Forever 2026 takes 3-5 hours per full clear (with hard modes) for a competent guild, and you need a minimum of 20-25 geared 80s to start. The hardest boss is Yogg-Saron + 0 keepers (the most prestigious achievement in the game). The most prestigious reward is Mimiron's Head (1% drop, only on hard mode).

Ulduar overview and requirements

Raid basics

Location: The Storm Peaks, in the Ulduar complex.
Raid size: 10 or 25 players. This guide covers 25-man.
Difficulty levels: Normal (10/25), Heroic (10/25) for the 11 hard mode bosses.
Boss count: 14 (11 normal + 11 hard modes, with shared hard mode triggers).
Boss order: Flame Leviathan → Ignis the Furnace Master → Razorscale → XT-002 Deconstructor → The Iron Council → Kologarn → Auriaya → Hodir → Thorim → Freya → Mimiron → General Vezax → Yogg-Saron → Algalon (optional).
Final boss: Yogg-Saron (or Algalon if you unlock him).
Loot: Tier 8 (200 iLevel) for first half, Tier 8.5 / 9 (213-226 iLevel) for second half, plus 258 iLevel hard mode pieces.

Attunement

Ulduar has no attunement in WotLK 3.3.5a. You can walk into the raid at 80 with no prerequisite questlines. The only requirement is being level 80.

Recommended gear for Ulduar 25 normal

Minimum: iLevel 226+ (Tier 7.5 set + crafted epics). Recommended: iLevel 232+ (Tier 9 mix from ToC 10). Optimal: iLevel 245+ (Tier 9 4-piece + weapons).

A fresh 80 with Tier 7.5 set (from Naxxramas) can clear the first 8 bosses in Ulduar. The last 6 bosses (Hodir + Thorim + Freya + Mimiron + Vezax + Yogg-Saron) require 232+ iLevel.

Boss 1: Flame Leviathan (the vehicle fight)

Health: N/A — vehicle fight.
Key mechanic: 3 vehicle types (siege engine, demolisher, anti-air gun). The raid must use vehicles to fight the boss and the adds.
Tactics: 2 siege engines + 2 demolishers + 1 anti-air gun is the standard composition. Save cooldowns for the tower phase.
Loot tier: 226 iLevel pieces.

Quick tip: The vehicle fight is unique in WotLK. Pre-assign vehicle roles before the pull.

Boss 2: Ignis the Furnace Master (the elemental)

Health: ~6.5 million HP (25-man normal).
Key mechanic: Slag Pot — Ignis puts a player in a pot for 10 seconds. The pot does 4,000 damage per second.
Tactics: Burn the boss. The "in the pot" player gets cooldowns.
Loot tier: 226 iLevel pieces.

Quick tip: The pot mechanic is the only tricky part. The pot target uses cooldowns to survive.

Boss 3: Razorscale (the flying drake)

Health: N/A — boss has multiple phases.
Key mechanic: Air phase — Razorscale flies and shoots fire. The raid must dodge. Ground phase — the boss lands and the raid burns.
Tactics: Phase 1 (air): kite. Phase 2 (ground): burn.
Loot tier: 226 iLevel pieces.

Quick tip: The air phase is scripted. Pre-position the raid to dodge the fire.

Boss 4: XT-002 Deconstructor (the robot)

Health: ~8 million HP (25-man normal).
Key mechanic: Heart phase at 75%, 50%, 25% — the boss exposes his heart, doing 50% more damage. The raid must burst the heart.
Tactics: Burn the boss. At each heart phase, the raid does max DPS for 30 seconds.
Loot tier: 226 iLevel pieces.

Quick tip: The heart phase is a DPS check. Save cooldowns for the heart.

Boss 5: The Iron Council (the multi-boss)

Health: ~3.5 million HP each (3 bosses) (25-man normal).
Key mechanic: 3 bosses share HP. The raid kills them in any order.
Tactics: 3 tanks, 1 each. Burn them simultaneously.
Loot tier: 226 iLevel pieces, including the Stormbinder's Boots (a BiS cloth piece).

Quick tip: The 3 bosses are tuned similarly. Burn them evenly.

Boss 6: Kologarn (the giant)

Health: ~10 million HP (25-man normal).
Key mechanic: Arms — Kologarn has 2 arms that need to be killed. The arms have independent HP. After both arms die, the raid is free to burn Kologarn.
Tactics: Off-tank each arm. Burn the arms. Then burn Kologarn.
Loot tier: 226 iLevel pieces, including the Twilight Missile Amplo (a BiS ranged weapon).

Quick tip: The arms are the key. Kill them first.

Boss 7: Auriaya (the beast)

Health: ~7 million HP (25-man normal).
Key mechanic: Sanctum Sentries + Feral Defender — the boss summons adds that need to be killed.
Tactics: Off-tank the adds. Burn the boss.
Loot tier: 226 iLevel pieces.

Quick tip: The adds are easy. The boss is easy. This is a "gear check" fight.

Boss 8: Hodir (the keeper)

Health: ~7 million HP (25-man normal).
Key mechanic: Flash freeze — the boss does a 12-second AoE freeze. The raid must burst heal through it.
Tactics: Burn the boss. Save cooldowns for the freeze.
Loot tier: 226 iLevel pieces, including the Leggings of the Wayward Conqueror (a BiS plate piece).

Quick tip: The freeze is a healer check. Save cooldowns.

Boss 9: Thorim (the keeper)

Health: ~8 million HP (25-man normal).
Key mechanic: Arena phase at 100-90% — the boss spawns adds in an arena. The raid must clear the adds while saving the boss for the kill phase.
Tactics: Phase 1 (arena): clear adds. Phase 2 (arena → boss): burn Thorim.
Loot tier: 232 iLevel pieces, including the Wisdom's Hold (a BiS mace).

Quick tip: The arena phase is the only mechanic. The adds are scripted.

Boss 10: Freya (the keeper)

Health: ~8 million HP (25-man normal).
Key mechanic: 3 adds at 100%, 60%, 20% — the boss summons 3 elemental adds. The raid must kill them.
Tactics: Burn the boss. Off-tank the adds. AoE them down.
Loot tier: 232 iLevel pieces, including the Ironmender (a BiS shield).

Quick tip: The 3 adds are scripted. Each is harder than the last.

Boss 11: Mimiron (the keeper)

Health: ~7.5 million HP (25-man normal).
Key mechanic: 4 phases — the boss is a 4-phase robot fight. Phase 1: Leviathan tank. Phase 2: Aerial Command Unit. Phase 3: V-07-TR-0N. Phase 4: Vezax.
Tactics: Phase 1-3: each component is a separate fight. Phase 4: burn the boss.
Loot tier: 232 iLevel pieces, including the Mimiron's Head (a 1% drop on hard mode).

Quick tip: The 4 phases are scripted. Mimiron's Head is the rarest drop in Ulduar.

Boss 12: General Vezax (the humanoid)

Health: ~8 million HP (25-man normal).
Key mechanic: Shadow crash — the boss does a 6,000 shadow damage to all players every 5 seconds. The raid must stack for the heal.
Tactics: Burn the boss. Stack during the crash.
Loot tier: 232 iLevel pieces.

Quick tip: Stack during the crash. Spread during the other mechanics.

Boss 13: Yogg-Saron (the final boss, with hard mode)

Health: ~12 million HP (25-man normal, with 4 keepers alive).
Key mechanic: 4 keepers (Freya, Mimiron, Thorim, Hodir) — each keeper can be "helped" to weaken the boss. Killing a keeper weakens the boss further. The "hard mode" is 0 keepers alive (kill all 4), which is the rarest achievement in the game.
Tactics: Phase 1 (0-30%): burn the boss, manage the adds. Phase 2 (30%): Sara phase. Phase 3 (40%): madness phase.
Loot tier: 245 iLevel pieces, including the Yogg-Saron's Hard Mode Reward (a BiS weapon).

Hard mode: Kill all 4 keepers before the boss reaches 30% HP. The "Make It Count" achievement (0 keepers alive) is the rarest achievement in WotLK 3.3.5a.

Quick tip: Yogg-Saron is the most-mechanically complex fight in WotLK 3.3.5a. The hard mode (0 keepers) requires extensive raid coordination.

Boss 14: Algalon the Observer (the optional secret boss)

Health: ~12 million HP (25-man).
Key mechanic: Algalon is a "secret" boss unlocked by completing a quest chain. The boss does massive AoE damage that requires the raid to stack.
Tactics: Stack for the AoE. Phase 2 (Cosmic Smash) requires raid-wide cooldowns.
Loot tier: 232 iLevel pieces, including the Astral Band (a BiS ring).

How to unlock Algalon:

Complete the "Archivum Data Disc" quest (drops from any Ulduar boss).
Use the disc at the Archivum Console in Ulduar.
Defeat Algalon within 60 minutes of the disc being used.

Quick tip: Algalon is the most prestigious kill in WotLK 3.3.5a. The "He Feeds On Your Tears" achievement is required for Glory of the Raider.

The Ulduar hard mode tier list (2026)

Hard modes in Ulduar are triggered by specific actions during the fight. The "rarest" hard modes (most prestigious rewards):

Hard mode	Trigger	Reward
Yogg-Saron + 0 keepers	Kill all 4 keepers	Yogg-Saron Hard Mode Weapon (BiS)
Mimiron hard mode	Don't use siege during Leviathan phase	Mimiron's Head (1% drop)
Freya hard mode	Kill 3 adds in 60 seconds	258 iLevel weapon
Thorim hard mode	Don't enter arena	258 iLevel weapon
Hodir hard mode	Don't freeze anyone	258 iLevel weapon
General Vezax hard mode	Kill the saronite animus	258 iLevel weapon

The "complete hard mode" achievement is the rarest, requiring all 11 hard modes in a single lockout. Awarded to less than 1% of 25-man guilds.

The fastest Ulduar 25 full clear path (2026)

The fastest guild progression path in 2026:

Week 1-2: Clear first 8 bosses (Flame Leviathan through Hodir) weekly. Gear up.
Week 3-4: Add Thorim + Freya + Mimiron to the clear.
Week 5-6: Add General Vezax + Yogg-Saron to the clear.
Week 7-8: Attempt hard modes (start with Thorim + Freya).
Week 9-10: Attempt Algalon + Yogg-Saron hard mode.

A new guild can expect 6-10 weeks to a full Ulduar 25 normal clear. A veteran guild with pre-BiS players can do it in 2-3 weeks.

Frequently Asked Questions

How long does a Ulduar 25 normal clear take on WoW Forever 2026?

3-4 hours for a competent guild. The first 8 bosses are quick; the last 6 bosses (Hodir + Thorim + Freya + Mimiron + Vezax + Yogg-Saron) take 2-3 hours.

What is the minimum iLevel for Ulduar 25 normal?

226 iLevel for the first 8 bosses, 232 iLevel for the last 6 bosses.

What is the hardest boss in Ulduar 25 normal?

Yogg-Saron (3 phases, multiple mechanics). The hard mode (0 keepers alive) is the rarest achievement in the game.

What gear do I get from Ulduar 25 normal?

Tier 8 (226 iLevel) for the first 8 bosses, Tier 8.5 / 9 (232 iLevel) for the last 6 bosses. Plus 258 iLevel hard mode pieces (Mimiron's Head, Yogg-Saron weapon, etc.).

What is Mimiron's Head?

A 1% drop from Mimiron hard mode in Ulduar 25. The mount is one of the rarest in WotLK 3.3.5a, expected 100-300 kills per drop.

Should I run Ulduar 25 before ICC 25 normal?

Yes, always. Ulduar is the second 25-man raid tier in WotLK 3.3.5a. The Tier 8.5 set pieces are pre-BiS for most specs.

Conclusion

Ulduar 25 is the most-mechanically-complex 25-man raid in WotLK 3.3.5a and the second 25-man tier in 2026. The 14-boss progression takes 3-5 hours per clear (with hard modes), and a new guild can expect 6-10 weeks to a full clear.

The hardest boss is Yogg-Saron + 0 keepers (the rarest achievement in the game). The most prestigious reward is Mimiron's Head (1% drop, only on hard mode). The hardest normal-mode boss is Mimiron (4 phases, requires coordination).

If you're preparing for Ulduar 25 on WoW Forever in 2026:

Pre-raid BiS gear first — see the WoW Forever Pre-Raid BiS Gear List for Every Spec (2026) guide.
Clear Naxxramas 25 first — see the WoW Forever Naxxramas 25-Man Raid Guide (2026).
Practice the first 8 bosses on alts first — they're a clean ramp-up.
Plan a full clear night (3-4 hours) with 22-25 players.
Work up to hard modes and Algalon over 4-6 weeks.

Once you kill Yogg-Saron + 0 keepers, you'll have a BiS weapon and one of the rarest achievements in the game. That's the milestone before ICC 25 normal.

Plan 6-10 weeks. Get the Tier 8.5 set. Attempt the hard modes. Mount up on Mimiron's Head.

Sources and references used in this guide: WotLK 3.3.5a Ulduar encounter mechanics from public theorycrafting, public WoW Forever realm Ulduar clear logs, and the WoWHead WotLK Ulduar Index.