All Implacables feature a main armament of four 150PW particle beams arranged in back-to-back pairs, one pair forward, and one aft. Each pair shares a common power source running through the height of the hull, economizing on weight. Additional armament varies from ship to ship, with a forward assault battery usually comprising either a plasma cannon or a torpedo launch bay. Merciless is armed with a 650PW plasma cannon. Two spacious hangar bays between them hold up to eleven ground attack craft, each able to land a full platoon of marines.
The main storage and engineering spaces are enclosed by twin lateral keels, with the main living accommodation situated in one deck lying over the top. A large dorsal pod houses the primary hopper drive, with communications and sensor arrays in a ventral pod. Twin lateral pods hold the secondary reaction drive.