[ngreen]

With water based games a lot of teams would have to be thinking about some new terms.

Bouyancy is the first term. If you want it to float above or in the water, or if you want it to sink, this will be important to you're plans.

Drag Force, the ability to move fast under water will rely a lot on minimizing your drag. Water has a much higher viscosity than air and factors a lot more into your movement. Earlier someone mentioned dolphins and how quick they move through the water. One way they do this is by changing the surface of their skin to minimize drag. Submarines have tried to use different chemicals to minimize drag on the hull. Shape and materials will be important for this.