It inhabited the Tars Lamora prison colony until 2383, when it was found by Rok-Tahk. Rok-Tahk gave it the name "Murf" and took it to the USS Protostar. Murf was fond of ingesting random pieces of mechanical equipment. (PRO: "Lost and Found")
At one point, Murf attempted to eat a photon grenade which later detonated inside of it, causing Murf to briefly expand in size before returning to normal, prompting Rok-Tahk to conclude that Murf was indestructible. (PRO: "Kobayashi").
Later still, while the Protostar crew were experimenting with the ship's transporter, Rok-Tahk suggested Murf be the first lifeform to try using the transporter, as its indestructible nature would reduce the risk of an accident. Murf was accidentally beamed out onto the outer hull of the ship, proving it could also survive in the vacuum of space. (PRO: "First Con-tact")
- PRO: Every episode
Murf's vocal effects were provided by Dee Bradley Baker.