Those guys that don't understand this game, you have to rearrange the tiles until each tile has the same amount as neighbouring tiles as the number on it.
Very easy.
1. Buy a dart monkey and put in middle. Upgrade Piercing Darts.
2. Keep buying dart monkeys and upgrading for the next 40-42 rounds.
3. Sell dart monkeys in the middle for supermonkeys.
I ended up with 41 dart monkeys with Piercing Darts, 1 normal dart monkey and 3 supermonkeys.