They swim around aimlessly, normally within sight of other Titans. In return the Symbiotes remove parasites from the Titan's body and mob potential predators that approach the Titan.
The Symbiotes lay their eggs within a gel-like substance in the Titan's tail hollow where the eggs are protected and can extract nutrients and oxygen. The Titan Holefish lives in a symbiotic relationship with a small aggressive fish known as the Symbiote. The gel serves as a nest for the Symbiotes to lay their eggs within, affording protection and transferring essential nutrients and oxygen. The hole is partially filled with a transparent light-blue gel whilst the center is completely empty, leaving a large enough gap for the player to swim through. The most defining feature of the Titan Holefish is the hole in the side of the body that the name is derived from. The tail fin is blue in color and very large, being taller than the entire body of the Titan though not very long. The green coloration continues down the front of the body until it meets the tail fin. The face portion of the body is a bright green and features two small blue eyes and a small, toothless mouth.
The body is mostly blue in color, darker towards the top and gradually lightening to white towards the bottom. The Titan Holefish's body is mostly circular and laterally flattened.
