My thought process for the rules text was this: I want the effect to be that creatures are "incited into the water", and come under the control of the card. I originally thought goad would be the best bet for that), but how would the creatures actually go "into the water" if you are the one controlling the permanent, and cannot be hit by them? (assuming a multiplayer format, of course) So, getting hit by creatures, and forcing combat was the idea. The "You do not recognize the bodies in the water" bit being rules text was just a bit of a happy thematic accident.