lol, I don't use formulas or anything. I been playing for 3 years and am a Diamond Wand on it right now.
Seriously this game is amazing if you have friends to play with. As this is a team game friends make this game 100x more fun
I quit because all my friends quit. I also sold the Diamond wand for like 400 USD (I sold it too cheap -.-)
Give this game a try and if you make friends and join an active guild you will definitely have fun!