A quick jump back whilst forming
Suiton:Suijinheki - Huge wall of water used to defend that can be made were no water is.
As the Suijinheki dissapates, I swim under water and out of range. Once back up I hold Suijin-Sama in front of me. "This is my last move, I'm out of chakra, the match is yours if I don't get it here". Using Suijin-Sama, all the water in the area is evaporated and gathered close to me, then...
Suiton:Teppoudama - A large sphere of water that is spit out of the users mouth. Considering I'm using all your lake for this... this is large.... very large. It engulfs the entire area and rushes towards Zabuza!