Berberoka
About
It sits in the pool and drinks. The water goes down, and down, and the fish are left flapping in the mud, and anyone watching from the bank thinks about how easy that would be to collect. When enough people are standing in the pool bed, it opens its mouth. The flood is not deep. It does not need to be deep. It needs to arrive all at once, in a place where everyone is bent over with their hands full.
Stats
Save Rolls
Traits
Special Attack
Drink the Pool: no roll and no save. It empties a body of water over 1d3 rounds and cannot be stopped by damage. Fish strand, the bed is exposed, and it looks like an opportunity, which is the whole trick. Release: it lets go the moment three or more creatures are standing in the exposed bed, or the moment any single creature it wants is more than 20 ft from firm ground. Not before, whatever damage it is taking. 30 ft cone, save Dex Quick, fail save roll 3d6+3 bludgeoning, knocked flat and Repelled. Cooldown 3 rounds. Send one person in, or none, and it will hold the water for the better part of an hour, give up, and put it back. Grasp: bludgeoning, melee 10 ft, +4 to hit, 3d6+3.
Special Defense
Full or Empty: while it holds the water it is bloated, slow and attacks at Disadvantage - and it cannot be made to release early by damage alone. Emptied, it is quick and dangerous and has nothing left to throw. A party that forces it to spend the water early wins the second half of the fight. Of the Marsh: it cannot be tracked in swamp, bog or flooded ground.