"Good! Blue for me." So he scrapes those onto his side, raises his hand where he's got a notebook and pen. Flips to a decently empty page, and explains as he makes lines.

"Usually you can just do this with paper and something to write with, but we've got these, so I'm using them." Because why not make things more complicated. "You make two lines, two more going through them, and the task is to join three in a row. So, if I lay a coin here-"

He puts one down, middle left.

"Now you can put down, anywhere inside here."

Tidus circles around the grid for noughts and crosses. With a lot less crosses.