You need to add buttons to change the strategic of the helper, you may could put you friends to hit the strongest enemy, or the closer to they, or the closer to you, or the enemy with highest HP.
For grim622: That lvl 34 is soo easy dude, You just need to put the two big towers in the square of the center, then the towers both leave down his upper side to the left and right respectively and form and a letter V then put little towers in the squares of the botom and leave down his upper side to the big towers like a support pilar of a construction finaly left 21 balls inside the V jeje have a good day dude ;)