Think of it as a paintball gun without the messy paint. The Xploderz Water Pellet Guns shoot a super absorbent polymer that expands as you pre-soak it in water. After soaking the pellets in water you load them into a cartridge and mount it on your gun of choice. Some guns include the XBlaster 200, XStormer 1000, or the XRanger 2000 (pictured above). Good news, the H2Grow ammo is pretty cheap at about $7.50 per 500 rounds. Video of the Xploderz after the break.