1.) Start with 4 slingshots
2.) Put One in each corner (So you get as much of the map as you can)
3.) Make them not move.
4.) Buy a sniper and place him in the middle
5.) Upgrade All except the speed (Try getting them all to lvl 3 before buying a lvl 4 for any)
6.)Buy 4 more sling shots and let them roam
7) Buy any friends you want.
Works for Easy / medium
+ for a easy walkthrough!