System summary

Rules and progression impact

What this system does
Level 10,000 Boss (two health bars)
Key rules
Cthulu Spawned via prismatic shard during the storm window [every 2H 35M]. · Z | Eternal Rage: Ominous red scream that deals rapid damage to all nearby enemies. 10x ticks. - · X | Divine Beam - Boss will charge a beam for, before releasing it towards ALL enemies within range, causing constant damage to each player (10x ticks).
Important numbers
Level 10,000 Boss (two health bars) · Cthulu Spawned via prismatic shard during the storm window [every 2H 35M]. · Prismatic Shard must be crafted via Doran the Forge using 5 mythical materials (phantom lantern, dragon heart, Sea Beast heart, raijin core, saturn's ring) · This boss does NOT have a 20 minute despawn timer like the other bosses. It roams infinitely until death.
How it affects progression
Level 10,000 Boss (two health bars)
Related tools
Damage Calculator
Source confidence
Source-listed
Last checked
July 3, 2026

Sea Events

Source notes and moves

Cthulhu Boss (Unreleased) illustrated Haze Seas wiki reference card

Level 10,000 Boss (two health bars)

Cthulu Spawned via prismatic shard during the storm window every 2H 35M.

Prismatic Shard must be crafted via Doran the Forge using 5 mythical materials (phantom lantern, dragon heart, Sea Beast heart, raijin core, saturn's ring)

This boss does NOT have a 20 minute despawn timer like the other bosses. It roams infinitely until death.

The shard must be fed to a whirlpool in the sea that appears during storm.

Upon summon:

- Ocean becomes nearly black

- Forced nighttime begins. Until his death.

- Low rumble SFX starts

- Screen distortion affects all players for X seconds

Server Message: "Something ancient has awakened beneath the sea..."

Boss Behavior

- Cthulhu roams in a square pattern like Ghostship

- Uses slow walking animation while roaming

- If a player enters aggro range, Cthulhu stops moving and begins combat

- If all players leave range, Cthulhu resumes roaming

- Boss does not despawn on a timer

Boss has two lives/Health Bars.

Once the sea form is completely defeated, a cutscene will occur to all players within 2000-3000 stud range, then an explosion of VFX where he's resurrected and starts flying.

First Form: - Legs will be submerged in the water.

Z | Eternal Rage: Ominous red scream that deals rapid damage to all nearby enemies. 10x ticks. -

X | Divine Beam - Boss will charge a beam for, before releasing it towards ALL enemies within range, causing constant damage to each player (10x ticks).

C | Devilish Clap: Boss will clap his hands together (there will be a startup). After clapping, a MASSIVE explosion of shockwaves + water will emit, damaging everyone within range & knocking them backwards about 200-500 studs. (1x tick)

AIR FORM - This will be AFTER resurrection where he jump up into the air flying.

Z | Tornado Havoc: Boss will summon tornadoes on ALL nearby players. This will cause players to fly up into the air & be suspended/stunned for a short period of time. 10 ticks.

X | Air Prison: All nearby enemies will become trapped in a prison that brings the player closer to the boss. Deals 1x tick.

C | Eternal Rage: Ominous red scream that deals rapid damage to all nearby enemies. 10x ticks. -

Drops:

- 100% Abyssal Eye (Race V3, Abyssal Necklace, DDB/ Free DB)

- Guaranteed Legendary+ fruit to whoever deals most dmg (80% legendary/20% myth chance)

- 10% Abyssal Haki Color Change (Black-Purple)

- 5 Levels/250 Gems/500k$

Titles:

- Title "Slayer of the Abyss" - Defeat Cthulhu

- Title "Emperor of the Abyss" - Defeat Cthulhu 10 times

- Title "Knight of the Stagnant Abyss" - Deal the most damage to Chutulu

- Title "Bearer of the Abyss" - Obtain the Abyssal Haki Color

Sources

References for Cthulhu Boss (Unreleased)

Related tools

Check the decision from another angle

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