The Mark X was amongst 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. Popular customers for it were bored dictators and their subjects. However, they could be destroyed by laser scalpels if used correctly, as shown by a buzz droid in a gladiator tournament.
Viceprex Mirkovig Hirken of Stars' End owned a Mark-X, and often pitted it against other droids in combat at his prison. While traveling with Han Solo, the droid Bollux was one of the Mark-X's opponents. Bollux defeated the Mark-X by outsmarting it, with help from fellow droid Blue Max.
- Star Wars Adventures 6: The Warlords of Balmorra
- Classic Star Wars: Han Solo at Stars' End 3 (First appearance)
- Han Solo at Stars' End comic
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- 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