This odd creature shares the traits of both humanoid an turtle. Standing upright though hunched, it has a human-like face and eyes with the beak of a turtle. Its hands and feet are webbed and its body encased in a turtle's shell. Atop its head is a shallow depression that appears to be filled with stagnant water. This depression is surrounded by a tonsure of scraggly, unkempt hair.

Kappa are mischievous, and sometimes malevolent fey who delight in fooling unwary travelers and robbing them of their belongings, and in some cases, their lives (if the mood strikes them). Kappa can be found in or near any body of water near the shoreline, where they lair in submerged, hidden caves or grottoes. Fortunately, Kappa can be reasoned with and they enjoy contests of skill and athletics, particularly wrestling. If the intended victim of kappa mischief can manage to remove the water from the kappa's head in a contest of strength or trickery, the wily fey will submit and let the traveler continue on their way and even provide them with useful information about the area. When the water is removed, the kappa will honor its bargain and the immediately make its way to the nearest source of water to refill the depression. If the kappa remains without water in the depression for a 24 hour period, it will die. In order to remove the water from a kappa's head, the opponent must wrestle or knock the creature to the ground by either guile or a contest of strength. This is no easy feat as kappa are both strong and nimble, and have an uncanny sense of balance when it comes to keeping the water atop their head where it belongs. 

Kappa are also extremely adept at surprising and ambushing interlopers, particularly those whom they would be unable to reason with or use guile. The kappa will submerge itself in the body of water near its lair and wait until its intended victim passes nearby, then it will pounce from stealth and attempt to drag its prey into the water and drown it. 

Kappa are omnivorous and eat everything form vegetables to the flesh of humanoids, however they are particularly fond of cucumbers or horseflesh, and a gift (or trade) of either will be met wit great appreciation.