I originally didn't really like the incorporation of the theme, but after a few replays I did actually start feeling it. It's not the same experience when you try to play it slowly, so I'm glad that I tried it again and again.
The robots got stuck in walls, which was quite irritating.
With the pixel art, it's hard to distinguish details, but at least the color scheme was nice. The mine explosion really surprised me. It's great, but you should give it more time before destroying it.
Unfortunately, no audio and music. At least adding some energetic music would go a long shot in making the player feel pressured to play more like I did on my later playthroughs.
Great job!