Your search for "Dueling Grounds 331" revealed the following:
Plains (331) (Foil) (8ED) from Eighth Edition, available at 401 Games Canada. Rarity: Common Finish: Foil Artist: John Avon
Built for head-to-head showdowns, the Invincible two-player playmat expands the premium format into a shared battlefield presentation. It should be positioned as a larger play surface that carries the same core benefits as the single-player mats—smooth card movement, strong print...
Built for head-to-head showdowns, the Invincible two-player playmat with Learn to Play overlay expands the premium format into a shared battlefield presentation. As a larger play surface for two players, it delivers the same core benefits as the single-player mats,...
Dueling Grounds (Foil) (INV) from Invasion, available at 401 Games Canada. Rarity: Rare Finish: Foil Artist: Pete Venters Card Text:No more than one creature may attack each turn.No more than one creature may block each turn.