This is actually a player mod that adds the Royal Guard Interceptor (from the discontinued Star Wars Galaxies MMO) to XwA's skirmish mode. It's not exactly an easy or straightforward process to add mods to XwA, and you actually have to replace one of the existing ships in your list (I chose to replace the Tandem X-Wing). It is essentially a TIE Interceptor with shields, but with the potential to be even faster and more maneuverable if you divert shield power to engines. Royal Guard Interceptors are, according to Expanded Universe lore, used by the best Imperial pilots to guard The Emperor in space.

This is probably my favorite ship to fly, and it was the only reason I ever put up with Star Wars Galaxies (which was an awful game, but the space combat expansion was...tolerable). I should have probably stacked it up against more X-Wings or even A-Wings for more challenge, because this ship dominates in dogfights.