This strange weapon looks less like a traditional whip and more like a tube of water, tapering along its length to icicle sharpness at one end. The handle is crafted from a pale blue crystal shard.

This +1 whip shimmers and undulates with deceptive grace when held. Unlike a normal whip, a water whip deals lethal damage and can affect armored creatures. Furthermore, while wielding a water whip, you are difficult to disarm. If the whip is knocked from your grasp, it immediately flows back into your hand at the beginning of your next turn (even if it is within someone else’s grasp) as long as it is within 30 feet of you. Doing this requires no action on your part. In addition, drawing a water whip is always a free action.
Both a fire elemental and water elemental are bound within a water whip, allowing it to emanate either of two energy properties, flaming or frost. You choose the property when you activate the whip, and it deals an extra 1d6 points of the appropriate kind of damage (fire or cold).

Lore: The first water whip was created by a sahuagin druid named Ak’ash’eck, who roamed the fringes of a great reef a decade ago (Knowledge [history] DC 20).

Prerequisites: Bind Elemental (ECS 51) or Craft Magic Arms and Armor, planar binding.
Cost to Create: 10,000 gp (plus 301 gp for base item), 800 XP, 20 days.