Katsuya's competitive grin and motion to grab his own fist in anticipation is, perhaps, just a little hindered by the fact that he's in a cute dog kigurumi.

Apparently not hindered himself, he grins and starts for the console. "Heheheee..Yer on then..! Sounds perfect!"

And really, it is- not really too much strategic need beyond a particular point there, and if Kaiba challenged Katsuya to a game of luck, it could go in any direction at all.