The USS Wolf (NCC-3921) was a Ptolemy-class transport/tug on active duty in the 23rd century. (Star Fleet Technical Manual) In mid-2293, Wolf was sent to the fourth planet of UFC 61033 to provide aid and assistance to the planet's surviving inhabitants. (Star Trek: Avenger: "The Dying of the Light") Wolf was involved in the recovery operation after the attack on Starbase 29 by an energy creature in 2294. It was also part of the task force that destroyed the creature. (Star Trek: Avenger: "Aftermath")