Added three new power-up items; the SpeedUp, which doubles the player's movement speed for 10 seconds, the Unlimited Ammo power-up, which does exactly what it says, but only for the Assault Rifle, Shotgun, and Flamethrower weapons, and the Extra Life power-up, which also does exactly what it says. There is a base chance of 10% for a power-up to drop off of a "special" zombie (Upchuck, Gasbag, Big Mama), with a bonus 10% chance per "tier" of zombie (ie: 20% for Gasbag, 30% for Big Mama).