Hi ribbit,
There wouldn't be any intestered in picking an inflatable character if it doesn't inflate anytime during the game ;P

Actually, this is not what happens in the game, each size is interpolated by stretching the previous frame until it fits the new one. The stretching looks pixelized too, ribbit, since it's not a flash game.

The "life bar" is indicated by the amount of air (or other gaz) you hold.