Divide players into two teams using different colored uniforms.
Game begins as a 1-on-1. Every 10 seconds a new player enters the game creating a 2-on-1, then 2-on-2, then 3-on-2, then 3-on-3, then 4-on-3, then 4-on-4.
Once you reach 4-on-4 remove a player every 10 seconds until you're back to 1-on-1.
Players should work on creating time and finding space with and without puck.