Tracker is a name used by several unrelated characters in the DC Universe. The original was a three-headed dog belonging to the New God assassin Tyrus of Apokolips. There is a manhunter named Mr. Longshadow who uses this name and was hired by the Penguin during Contagion. Nicholas Kazantkakis took the name to fight Batman as a member of the Network. In the Navy SEALs, there is a notable soldier named Trachsel who used the nickname while partnered with Jonah "Ice" Berg.