I found a way to reach and probably kill any queen with only 1 com as unit! I tested it on very easy level chickens and won with 1 com. I was going to reach queen on suicidal but after 40 mins of my strategy, people called vote for exit due to boreness.
My way is: Simply level down a very small area where you com is with terraforming. Dig the deepest possible. Many chickens will eventually reach you but won't fire at all. However after a certain time they die and they will damage you. You might very likely survive. And if you have repair kits, I don't see how you can die.
The little chickens that run fast and bomb will kill all chickens over water, and I'm guessing the queen too.
It seems that in the very easy level the queen is a white dragon. In my game the white dragon went under water and passed through the ground and died instantly, making a win for me. (I was using relay host so this win isn't counted).
This strategy might serve as a backup if a whole team fails at some point. Dig up to China! Or hell XD