You send a blast of water at your opponent, using the source of water below you.
EXP Cost: 5 EXP
Benefit(s): By using a body of water which at least reaches to your waist (for a medium creature) you can, as a full-round action, send a torrent of water as a ranged attack at anybody within 12 squares of you. This attack deals 10d6 + your Constitution points of cold damage. After using this attack, the water disappears (or in the case of a lake, it is reduced to waist-high water and can be used one more time).
This costs 2 from your Hamon Pool to use.