Changes to iphone game

I have just recently launched the IOS game Avalanche Mountain into the App store. The game is a snowboarding game When originally developed I wanted the game to have an avalanche that would chase the skier/snowboarder. If time ran out then the snowboarder would be consumed by the avalanche. My original developer could not do this. I need someone that can and do it well. Also want the ability to do the following tricks in the game for additional points 1. Left or right board grab 2. Flips 3. Nosegrab and Tailgrab 4. 1 or 2 while doing a flip