Niv-Mizzet, Chess Master

Flying
When Niv-Mizzet enters the battlefield, you
and target opponent play a sub-game of chess.
Whoever wins the sub-game creates 8 1/1 pawn
tokens, 2 2/1 bishops, 2 1/2 rooks, 2 2/2 knights,
1 3/3 Queen, and 1 4/4 King with first strike.
"Checkmate."