Great fun!
Is this your first machine code game? If so how did you take the step from MPAGD to ASM?
Small bug, though it's kind of cute: the score should be stored as a 16bit number as it overclocks at 255 ÷)
Ahhhh good spot - user testing was limited! I actually coded the game in boriel basic. I've written a few c64 games in machine code, but yet to take that step on the speccy.