This is a 2 player subtraction game, that could be used as a center. It has the rules for the center included. The students will play this game very similar to war, where they will draw two cards from the top. Then, they will subtract the two cards and whoever has the largest difference gets to keep the hand drawn.
There is a set of cards for 2-digit play, or 3-digit play or both. It is highly recommended that you laminate the cards for repeated plays.
There is a poster for the rules at the center, along with the learning goal: I am able to subtract within 1000 using models and strategies.
My students love playing this game, and the best part is that they are practicing the skill of regrouping! :)