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[edit] Power-ups

You'll find that destroying boxes and blowing up enemies will sometimes yield small flashing green objects. These represent various upgrades you can get (minus the cash bonus). The following is a list of all the power-ups in the game:

Name	Effect
Ammo	Increases your total ammo. Only affects upgraded weapons.
Auto	Makes your normal gun fully automatic. Just hold fire.
Baz	The bazooka is a single, very strong laser projectile that can go through multiple enemies. It is the strongest weapon in the game.
Score	Gives you bonus cash (points).
Flame	A flame thrower that extends from your gun. Uses a lot of ammo, but is good against large targets.
Laser	A rapid firing projectile that is stronger than the regular gun.

[edit] Vehicles

Throughout the game you'll come across turrets and vehicles that you can control. Simply jump near them to attach yourself to them, and jump again (sometimes in combination with the ) to unjoin yourself from the vehicle. All vehicles have their own health (although some are invincible), but when they aren't being controlled, they can only be destroyed by you.