You can attack a square within range, and trigger it to explode later like a primed explosive.
EXP Cost: 3 EXP
Benefit(s): Make an attack within your blast's range against the ground (Reflex Defense of 5) and on a successful hit, the square is primed and charged with your energy. The next target which steps on that square within the next day will trigger the explosive, and have an attack made against their Reflex Defense (using your attack modifier) to deal damage. The target is flat-footed unless they willingly and knowingly step on it.