Enable cheats and then type one of the following codes to gain extra ammo or attacks:

10 TNT = !haunt haunt haunt

20 Fly Swatters = !harsh language

30 Mines = !sprinkles

3 Air Attacks = !heavenly glory

3 Baseballs = !one time...

3 Napalm Air Strikes = !this one goes to eleven

Bug Spray = !henry

Hammer Mines = !spiny norman

Heavy laser = !hello neo

Laser upgrade for your primary weapon = !mib