Cratos was one of several UNF vessels that was sent to scout the Independent systems, bordering Imperial space, to ensure that they had been fully evacuated. As it patrolled the Iliad system, it came across a drifting escape pod. The crew risked a pick up, discovering Natalia Grace was aboard.

In 2621, Cratos participated in phase two of Black Widow. When the general retreat call was issued, it attempted to jump out of the system, shielded from attack by the Black Orchid, which sacrificed itself to allow the dreadnought to do so. Cratos was chased into its jump point by a number of Pandoran starfighters, that attacked the engine block at the rear of the ship and forced it to revert back to normal space. Cratos emerged almost a year beyond the edge of the Adetton system and was forced to spend the next twelve months making the return trip to pick up navigation settings from the buoys located there.

Cratos was believed to have been destroyed during Black Widow and so embarked on a series of covert missions, dressing itself up as a Pandoran vessel known as Sandwalker (the ruse being Natalia Grace's idea). In late 2624, the Sandwalker travelled to the Kethlan system, intending on capturing Jason Zackaria. It arrived too late, and returned to Sol with Griffin and the rest of the Parks' fleet.

Parks hijacked Cratos from Sol, taking it to HD 21563010 in order to search for the Elpis' Gift. Since Cratos had been under covert operations and had not been integrated into the allied forces' vessel catalogue, it was immune to the remote fail-safe system termination commands that could be used against other CSN and UNF vessels.

Both Ali Liu and Karen Weathers came aboard during Cratos' trip to HD 21563010. The dreadnought was attacked by Chimera around HD 21563010 Ab, but was saved from destruction when Parks rammed the Elips' Gift into the Imperial carrier.