I love the rust mechanic, and the graphics and soundtrack work really well together.
As other commenters have pointed out, the rust mechanic can create a negative feedback loop, where I simply can't advance further.
I'd love to see a couple tweaks to that mechanism, as well as a sound fx that emphasizes the rust build-up (like rusty grinding gears gaining in volume and adding psychological pressure).
Or maybe something that made the decision of where to quit a strategic choice -- like if on the next run you can use the last robot's body for spare parts?
In any case, that's all nitpicky stuff -- it's a fun game, and nice job putting this together within the time limit!