The USS Incursion (NX-74808) was a variant of the Defiant-class operated by Starfleet Intelligence and commanded by Captain Marcus Refelian.
The main feature of the Incursion was the use of the prototype holographic masking system, which allowed the ship to change its appearance.
The ship played a key role in exposing and stopping the threat of a rogue group of Vulcans, called the Wardens. (TNG game: Star Trek: Away Team)
USS Incursion (NX-74808) article at Memory Beta, the non-canon Star Trek wiki.