Yu-Gi-Oh: The Falsebound Kingdom for the Gamecube. Notable in that I'd like to believe it was to YGO what
Starfox Adventures was to Starfox; an attempt at making a different game altogether (let's call it "
Kingdom," after the game-within-a-game here), with the more popular franchise label tacked on for sales purposes.
To summarize,
Kingdom is a RTS/RPG game, where field movement between bases and objectives is in realtime, but battles are turn based. You command several generals (YGO characters), who themselves control three monsters in battle, to capture objectives from enemy generals. And instead of battles being 'to the death' as it were, each monster under your command had a specific number of turns it could take per engagement. Should the battle end without one side being wiped out (which was frequent... at least early-game), the winner would be decided by points, and the forces would separate, making the idea of a fighting retreat actually possible.
It was a pretty interesting game, if massively unbalanced and in need of some serious polish. And it had this
kickass theme. I'd like to see what'd happen if the developers got more funding, time, and experience and remade
Kingdom anew... without the Yu-gi-oh characters and monsters tacked on.