I was really torn on whether to extend the gameplay time leading up to the boss fight, to give the player more time to get used to the mechanics, but in my last game jam, few people gave the game a real chance and only played the first few minutes. So, I decided to make the experience shorter; a match now takes about 3 minutes, whereas before it was 5. Looking back, maybe 5 minutes would have been better after all.
Anyway, thanks for the feedback. Even though I like the chaotic vibe, a bit of breathing room was definitely needed. I'm glad you enjoyed the experience and were surprised by the dragon.