So what I came up with was that within every 3 months, if you are born there then you get that power. For example, if born in January, February, March you get Solid Manipulation, and the next three months you get liquids, and so on and so forth. The days determine what variation of the power you get. For example, January 1 gives you earth manipulation. I feel like I'm missing something important! What flaws do you see in this system?