The Giant Merman, as the name suggests, is a large Merman that serves as the boss of the Aqueduct of Dragons in Castlevania: Harmony of Dissonance.


The Giant Merman has control over bodies of water. It stops for a moment, builds up energy and unleashes a wave of water that travels along the room. It then jumps and curls into a ball, rolling fast toward Juste, attempting to run over him. Next, it will summon the aid of a group of either Mermen or Fishmen, and command them to attack him.


This boss is weak to Ice, so attaching the Blue Stone to the Vampire Killer will deal the most damage possible to it. It has very predictable attack patterns overall and will always telegraph them by making little pauses before performing each one. The fight always starts with it conjuring and unleashing a wave of water; this is easily avoidable by double jumping over it, and it also doesn't have very high reach. The player should take advantage of this time to attack it constantly, only stopping to jump over the wave.

It will follow by curling into a ball and rolling at Juste. Just do a double jump and hit it with a dive kick to land behind it, Juste won't take damage this way even if the Giant Merman is in the middle of this attack.

Once it comes back to normal, it will stop for a moment and summon the aid of a group of either two Fishmen or four Mermen randomly. It is recommended to make good use of the player's available spell fusions at this moment to get rid of the auxiliary mob. A spell like the Soul of Hydra (summoned by combining the Fire Book with the Axe sub-weapon) can deal massive amounts of damage to all enemies. For this reason, it is also advised to save some spare MP for tight situations like these, and not waste all of it at the start of the battle.

Enemy Data

No. Name JPN Lv. HP
55 Giant Merman 30 3,520
Tolerance Weakness Common Drop Rare Drop EXP
Fire Ice - - 1,298
Location (Castle A) Location (Castle B)
Aqueduct of Dragons -



Castlevania HoD - Boss Fight - Giant Merman

Castlevania HoD - Boss Fight - Giant Merman

See also

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