The basic idea is good!
I found the AI a bit too smart - there is no difficulty ramp up as far as I can tell.
Note that you used an old version of Pico 8 - recent 0.2 version has a much better web export.
Thanks! I tried to adapt the difficulty but sometimes it's too easy or too hard... I'll try to find a workaround.
Thanks for the tip about Pico 8 export!