Dumb me. I should have made it clearer that the effect I was after is the following:
Players movement speed increases incrementally with every powerup they pick up. So, every time they pick up a powerup, they get faster, and faster, and faster.
Dumb me. I should have made it clearer that the effect I was after is the following:
Players movement speed increases incrementally with every powerup they pick up. So, every time they pick up a powerup, they get faster, and faster, and faster.