when your ants die, it cost food to rehatch them and when food runs out you can't spawn any soldiers back until you get more food back right? This is the same with the enemy colony in challenge 3, kill a bunch of their ants until their food has been diminished to the point where they can't hatch more, then enter their nest and kill their queen. put your black ants and leafcutters in the same group while the wood ants in another separate group, put the ants either in your area or around the center of the tube, and put your wood ants slightly more behind your melee ants. You have started challenge 3, with strong forces, decently stocked food and skill.