Algodoo

Fires four rockets, A and D to aim, F to fire. Does not support automatic fire, but God help you if you need to hit it more than once with these babies.
Rockets are balanced so that the best angle to fire at to hit the block is with the bottom corner of the purple block at the end of the barrel overlapping with the bottom side of the block marking the top of the build area.

I think I`m done with this now. Body is the same, launcher is tweaked just a bit, rockets are now much heavier and have secondary explosives besides the original warhead and propulsion, although they don`t always make a difference, especially against the target block I put up. Against the brick wall which I think they`ll be tested on, they can be catastrophic. Secondary explosives are in the non-colliding nose block that I built originally for balance, and are designed to bounce, drag, and stick to things while the springs holding them go nuts.

Wall not included due to bothersome lag, but if you want to use it, go look at A Mammoth`s artillery because I used his wall for personal testing.