Weirdly I just did it without getting hit after taking a break (and them jumped away without thinking and immediately died to fall damage) lol. I was using the SDMG with chlorophyte bullets, ranger, destroyer and avenger emblems, sniper scope, ankh shield and a star veil, which i guess ended up being pointless. No arena, just did it in the sky with cosmic car key.--Get Ankh Shield so those negative walls don't mess you over with debuffs
--Build the arena in the air when you fall down you reappear at the top
--if your playing summoner, build a few walls to the left and right of Purity Spirit, to block the null beams attacks, the attack that usually means gameover if you get hit by it. But by being summoner you can bypass the walls you built
Just a few tips
If your having trouble beating this boss you likely have no chance against the final 2 bosses but you likely could beat Spirit of Chaos just fine, I found myself using software to lower my FPS to beat Blushiemagic (before the nerf)
It died *way* faster than last time and I barely saw any Shields compared to usual... I'm wondering if there's something I haven't understood about when those are spawned in.