This is the most efficient way to kill the boss:
Go to one of the sides and stay there. After he shoots his comets up, he will charge you, so double jump above him. He will hurt you for eight damage and knock you out, directing you toward the center and he will get hurt, releasing gems that you pick up. This will work for almost all but until two lasers. Then, dodge his first attack and dash at the wall. + so everyone can get the badges!
It glitches. I died, but used something to repair at the last second. Now I have the little explosion on my character all the time, but I'm still alive.
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