Really fun idea! Doing levels "legitimately" was really difficult with the spikes and the fast movement, but I had lots of fun experimenting with combinations of upgrades to find an easy route that I could complete, and then adjusting the timing to give myself a challenge. Worked like a charm! Only made it to day 5 but it was because I was trying new strategies (and messing them up)
Full marks for innovation and theme. With more levels I would have just kept playing. Nice work!