Needs some work.
I love the fact you can position your drones, and you can play around with it rather than have everything click like a mad person and get sore fingers.
However, at later levels, even maxed out drones seem to do little damage, and you do end up clicking till you either lose or your mouse breaks.
It would be nice if when certain upgrades were purchased (like at level 1 of the multi-attack drones, large numbers of low health creatures would appear.) seperate events would trigger. Also, a larger trench or multiple trenches would be nice.
Please, always keep the game where you have to participate in it otherwise you lose, but dont make it a clicking frenzy.
Some drones that dont do damage but give effects (like slowing down/temporarily stopping the enemy, giving them a 'poison' type status amongst other things) would be something nice.
Keep expanding with this idea, it is a good one :)