I actually ended up really liking this. I think "10 enemies" refers to ten different enemies. I really appreciate all the hard work put into making this. It seems like there was a lot of detail. While not too colorful, still very good. I was afraid you'd have to collect all the coins to advance. I'm glad you don't.
I also like how your health can be replenished level after level. It's still pretty difficult. I had no idea slime could kill you in a game like this. It kind of reminds me of something like "Blue Ball Machine" with how small everything looks. That's a good way to show off detail.