I beat him on my first try, too! Honestly I didn't think he was that hard. He jumped around a lot and threw bombs a lot, but his damage output is much less than your output if you spam the Chaos Sphere relic, because they can hit him easily. You can also pogo off his pink beakers when he summons them. It should give you an easy time! Also, his boss fight is the GREATEST BOSS BATTLE EVER!