I can beat Wart, but the middle boss is unfair, and I genuinely don't know what to do on the Zelda 2 boss in this game.
Edit: Thank you for your help, BoMToons. I honestly did not think I'd ever do it, but I killed the Zelda 2 boss and Dark Link, both without taking damage. It took me a good few runs. I have yet to replicate that cool run. I also finally won the Abobo fight. I didn't like using the barrel last time because I didn't understand why it disappeared on the 5th throw, but I realized that's how many times I'm allowed to use it. It really did help me win as I used it a little differently, and fought similarly. I don't think I'm good enough to get 3 stars though. XD