Price (Item Level): 250 gp (2nd) (least), 1,000 gp (4th) (lesser), or 3,000 gp (7th) (greater)
Body Slot: — (armor crystal)
Caster Level: 5th
Aura: Faint; (DC 17) transmutation
Activation: —
Weight: —
This sea-green crystal always feels moist to the touch.
A crystal of aquatic action aids the wearer while underwater.
Least: Any armor bearing this augment crystal does not impose an armor check penalty on your Swim checks.
Lesser: As the least crystal, and you also gain a Swim speed equal to one-half your land speed (round down to the next 5-foot increment).
Greater: As the lesser crystal, and you also take no penalties on attacks or movement while underwater (as if under the effect of freedom of movement) and you can breathe water as easily as air.
Prerequisites: Craft Magic Arms and Armor, freedom of movement, water breathing.
Cost to Create: 125 gp, 10 XP, 1 day (least); 500 gp, 40 XP, 1 day (lesser); 1,500 gp, 120 XP, 3 days (greater).
Source: Magic Item Compendium, page 25.