|Difficulty Level||Hit Points|
|Pink on the Inside||130|
"Despite a stench that will keep you out of fish markets for the rest of your life, these mobile mounds of teeth are best encountered on dry land, out of their natural element. Underwater, they'll quickly show you the meaning of a stomping ground. They may even summon a few bone eels to help out. Fish food, anyone?" — Blood Beastiary
The Gill Beast is a Blood enemy. It is a giant, amphibious, highly aggressive creature, and the most menacing water hazard that Caleb will meet in his adventures. They have muscular fleshy bodies, flippered hands, and giant heads that are little more than a mouth with needle-sharp teeth. Their speed in the water makes them particularly dangerous, especially since they often travel with Bone Eels or other Gill Beasts and can surround you, blocking your path and making you drown. According to the Beastiary, they were supposed to be able to summon Eels in a similar way to the Mother Spider. If you plunge into the water and hear the roar of the Gill Beast, get out as soon as you can. They have no long range attacks, but can move twice as fast as you can in the water.
Gill Beasts can live out of the water, but without their natural element, they are slow and ponderous. A good tactic is to draw them onto the land where they are less of a threat.
The Gill Beasts have no known origins. They may be evolutions of the Bone Eel, servants of Tchernobog, or unrelated creatures. In one map, a room near the ending shows Gill Beasts in a cage alongside other humans, indicating they are either the subject or result of an experiment. They do not appear in Blood II: The Chosen which may indicate that they went extinct or the Cabal stopped, if they ever did, creating them.
"If you have to face a gill beast in the water, you're in big trouble. While slow and ponderous above water, in their element they are vicious adversaries." — Blood Manual