Bloodworms are a species of yellowish-reddish, large worm and leech-like creatures that lurk in the Barrows tunnels where they live in the darkness and feed on the blood of unwary treasure hunters. Bloodworms are one of the many obstacles between a player and the chest containing rewards where they constantly distract players from completing puzzles.
They spawn whenever the player opens a door in the tunnels. They are often ignored due to their lack of drops. Killing a bloodworm will increase the kill count by one. They are aggressive to any player regardless of Combat level.