The Mark X was among the best gladiator droids in existence. It was armed with a diverse array of weaponry capable of destroying almost any foe, and had heavy armor. Its multiple weapon-arms included a neuron whip, vibro-ax, blaster rifle, missile launcher, flame projector, and a primitive spiked club. Galactic customers for whom the droid was in demand included bored dictators and their subjects. The droids were not, of course, invincible and could be destroyed by well-aimed energy bolts or laser scalpels, if used correctly, as shown, on one occasion, by a buzz droid in a gladiator tournament.
In 23 BBY, Rigorra the Hutt deployed three missile-launching and flame-throwing Mark-Xs against bounty hunter Jango Fett in the warlord's hazardous subterranean "Impromptu Semiannual Balmorra Death Run" competition. Other captured bounty hunters who participated in the compulsory contest included Aurra Sing, Bossk, and Skorr. Because Fett was already familiar with the gladiator droid's vulnerable spot—the small underside patch that lay between the treads, where the droid's external cooling circuitry was located—he was able to cripple all three Mark-Xs with strategically aimed energy bolts. The areas between the Executioner droids' treads exploded, bringing them down.
- Star Wars Adventures 6: The Warlords of Balmorra
- Han Solo at Stars' End (First appearance)
- Han Solo at Stars' End comic
- "Galaxywide NewsNets"—Star Wars Adventure Journal 3
- A Guide to the Star Wars Universe
- Han Solo and the Corporate Sector Sourcebook
- The Essential Guide to Droids
- Star Wars Encyclopedia
- Arms & Equipment Guide
- The Official Star Wars Fact File 56 (EXE1-4, Mark X Executioner Droid)
- The New Essential Guide to Droids
- The Complete Star Wars Encyclopedia
- Galactic Gladiators: Great Warriors of Star Wars