Cloak Leader served as a TIE/LN starfighter pilot within the fleet commanded by Grand Admiral Thrawn around the time of 9 ABY.
This individual was in command of the TIE fighters and mole miners force concealed within the cloaked cargo bay of the Nartissteu as the Battle of Sluis Van began. Following the destruction of the A-class bulk freighter, Cloak Leader informed Captain Pellaeon that the command module of the freighter had managed to escape. Subsequently, Cloak Leader took part in the defense of the mole miners as they latched onto "rebel" ships, until Thrawn gave him the order to fall back to the Chimaera.