This is a 2-player game. You need to collect as many gems as you can in the time provided. Each time you collect a gem, the game time is extended for 1 more second. Be sure to avoid the walls and snowballs as you will crash if you hit them. You are also able to knock your opponent off the road and make them crash. Red car moves with W, A, S, D. Blue car moves with the arrow keys.
My video tutorial on how to make this with an explanation is found at: https://www.youtube.com/watch?v=2R2xEOXxQbE
