A new fan-made project has successfully ported the original Super Mario Bros. to the Game Boy Color, titled Super Mario Bros. Mini. Developed by homebrew developer Mico27, this version of the classic NES game includes several exciting enhancements and new features that expand upon the original experience.
Rearrange, not rescale, which would be neccessary for a non-multiple-of-8 tile size. I originally thought it was ¾ size (12×12), which would need to shift graphics data to cram 2 virtual tiles into 3 physical ones. Of course, scaling would also look terrible, everything needs to be hand-drawn.
From squinting at it, all the blocks appear to be 8x8.
Yeah, I only realized that once you posted it.