The Defel was able to sneak onto the Lady Luck and place two tracking devices, one on the hull and one inside the ship where it would not be found. Ferrier was thus able to follow Lando Calrissian and Han Solo to Pantolomin and help Grand Admiral Thrawn obtain the location of the Katana fleet.
Ferrier's wraith was present at the first meeting of the Smugglers' Alliance when Imperial lieutenant Kosk and his men attacked. The Defel was standing against a wall ready to hit the Imperials when they came in. (This would later help Gillespee figure out that Ferrier and the wraith already knew the stormtroopers would attack).
Later, the wraith sneaked into the Wild Karrde to plant evidence that Talon Karrde had hired Kosk and his men, but which ultimately proved Ferrier to be the traitor amongst the smugglers. When Ferrier ran, he left the wraith behind, a prisoner of the Smuggler's Alliance.