16 cards where the illustration contains “three-legs”

Arbalest Engineers (The Brothers' War #206)
Ashnod's Harvester (The Brothers' War #117)
Brood Butcher (Battle for Zendikar #199)
Combat Courier (The Brothers' War #77)
Core Prowler (Mirrodin Besieged #103)
Geothermal Kami (Kamigawa: Neon Dynasty #186)
Hexmark Destroyer (Warhammer 40,000 Commander #36)
Lurebound Scarecrow (Shadowmoor #256)
Myr Adapter (Mirrodin #210)
Salvager of Ruin (Core Set 2020 #237)
Scrapwork Mutt (The Brothers' War #164)
Skorpekh Destroyer (Warhammer 40,000 Commander #57)
Skorpekh Lord (Warhammer 40,000 Commander #58)
Swiftgear Drake (The Brothers' War #251)
Triskelion (Mirrodin #269)
Ulamog's Despoiler (Battle for Zendikar #16)

Though this query has ended, its relics still slumber in New Argive.