Haze Seas Cthulhu Boss Guide – Spawn, Moves, Drops

Cthulhu is the ultimate endgame boss in Haze Seas and easily one of the hardest encounters currently available. Unlike the other Sea 3 bosses, this fight isn’t tied to a simple timer or raid event. Summoning Cthulhu requires crafting a rare item first, waiting for the right weather event, and surviving a brutal two-phase battle. If you’re after Race V3 materials, exclusive titles, or some of the best rewards in the game, this is the boss you’ll eventually need to master.

Haze Seas Cthulhu Boss Guide – Spawn, Moves, Drops

  • Level: 10,000
  • Health Bars: 2 (Two Forms)

Cthulhu has two separate health bars, meaning the fight doesn’t end after defeating him once. Instead, the battle enters an entirely new phase with different attacks.

How to Spawn Cthulhu

Cthulhu can only be summoned during a Storm Window, which appears every 2 hours and 35 minutes.

However, simply waiting for the storm isn’t enough. You’ll first need to craft a Prismatic Shard.

How to Craft a Prismatic Shard

Visit Doran the Forge and combine the following Mythical materials:

  • Phantom Lantern
  • Dragon Heart
  • Sea Beast Heart
  • Raijin Core
  • Saturn’s Ring

After crafting the shard, wait for the storm event to begin.

Once the storm appears, locate the Whirlpool out at sea and feed the Prismatic Shard to it. This immediately summons Cthulhu.

What Happens When Cthulhu Appears?

The moment Cthulhu is summoned, the entire server changes dramatically.

Several world effects activate at once:

  • The ocean turns almost completely black.
  • Nighttime begins and remains until Cthulhu is defeated.
  • A deep rumbling sound echoes across the world.
  • Every nearby player experiences temporary screen distortion.

A server-wide message also appears:

“Something ancient has awakened beneath the sea…”

Unlike most bosses, Cthulhu does not despawn after 20 minutes. The fight continues until players successfully defeat him.

Cthulhu Boss Behavior

Before entering combat, Cthulhu slowly patrols the ocean in a square-shaped path, similar to the Ghost Ship.

Once a player gets close enough, the boss immediately stops roaming and begins attacking.

If every player leaves the fight, Cthulhu doesn’t disappear. Instead, he simply resumes patrolling until someone challenges him again.

Phase One (Sea Form)

During the first phase, Cthulhu remains partially submerged in the ocean while attacking players from the water.

Eternal Rage

Cthulhu unleashes a terrifying scream that rapidly damages every nearby player.

  • Multi-hit attack
  • 10 damage ticks
  • Large area of effect

Divine Beam

The boss briefly charges before firing a massive beam toward nearby players.

  • Hits every player within range
  • Continuous damage
  • 10 damage ticks

Devilish Clap

Cthulhu performs a slow wind-up before slamming both hands together.

The impact creates an enormous shockwave that:

  • Deals heavy damage
  • Launches players hundreds of studs away
  • Creates a massive water explosion

Phase Two (Air Form)

After the first health bar reaches zero, a cutscene plays for players within roughly 2,000 to 3,000 studs.

Following a huge explosion, Cthulhu resurrects and begins flying above the battlefield.

The second phase is significantly more dangerous than the first.

Tornado Havoc

Cthulhu summons tornadoes beneath nearby players.

The tornadoes:

  • Lift players into the air
  • Temporarily stun them
  • Deal damage over multiple hits

Air Prison

Nearby players become trapped inside a prison-like attack that drags them closer to the boss before dealing damage.

This ability makes escaping follow-up attacks much harder.

Eternal Rage

Cthulhu uses the same devastating scream from Phase One.

Anyone standing nearby will continue taking rapid damage unless they quickly move away.

Cthulhu Drops

Defeating Cthulhu rewards players with some of the rarest items currently available in Haze Seas.

Guaranteed Drops

  • Abyssal Eye (100%)
    • Used for:
      • Race V3
      • Abyssal Necklace
      • DDB / Free DB
  • 5 Levels
  • 250 Gems
  • $500,000

Rare Drops

  • Legendary or higher Fruit for the player who deals the most damage
    • 80% Legendary Fruit
    • 20% Mythical Fruit
  • 10% chance to obtain the Abyssal Haki Color (Black-Purple)

Cthulhu Titles

Defeating Cthulhu also unlocks several exclusive titles.

Title Requirement
Slayer of the Abyss Defeat Cthulhu once
Emperor of the Abyss Defeat Cthulhu 10 times
Knight of the Stagnant Abyss Deal the most damage to Cthulhu
Bearer of the Abyss Obtain the Abyssal Haki Color

Cthulhu is currently one of the most rewarding bosses in Haze Seas. Besides dropping the Abyssal Eye, which is required for several endgame upgrades, the fight also gives the highest-damage player a guaranteed high-rarity Fruit and offers a chance to unlock the exclusive Abyssal Haki Color. If you’re working toward Race V3, collecting every title, or chasing the game’s rarest rewards, Cthulhu should be at the top of your farming list.