This was pretty enjoyable and a fun use of the theme! The doodle artstyle works great and is clear for each upgrade in the gameplay despite being minimalistic. The preview is also a nice touch to know how the robot will work. Although I didn't much impact on the the gameplay, it felt enjoyable to watch the bots go, how they reacted to the physics and creating a combination that had the best chance to win.

Generally a cool concept, much like the series "Battle Bots" where the robots are built in a certain meta strategy and fight. 

One thing I will say is this is less of a game and more of a simulation. Still entertaining, but there is not much in the way of substance that makes it "playable" besides the choice you make at the beginning of each phase. I still do find this kind of fun, like betting on a horse, but that's pretty much all this boils down to I'm afraid. 

Would be very interesting to do some sort of genetic algorithm test on this though to find optimal builds