Biohazard by Mattsstuff (Extreme Demon) @liathecatto
Biohazard by Mattsstuff (Extreme Demon)  @liathecatto
Uploaded April 2026 | Updated September 2026, 2 weeks ago
This is probably the most unknown Nine Circles extreme demon above entry extreme difficulty, perhaps with the exception of I Cry due to that only being rated for a week or so. Admittedly, this is probably for good reason. This level has some of the most questionable hitboxes compared to its visuals and as such it gets a bit too much of its difficulty from that. Some of the deco spikes use different sized spike hitboxes than other deco spikes of the same size, and some don't even have any spike hitboxes at all. Some of the slope structures don't even visually travel at a 45 degree angle, which means you clip into the deco a LOT of the time which feels really unnatural. Playing this with hitbox on death is something I would highly recommend, but it was also really frustrating dying to a really open gap in the layout due to just simply having no clue at all as to what the hitboxes could possibly be from how inaccurate the deco is.

Some other issues include stuff like the transition at 42 just being blatantly broken as clicking to go up into the ball portal too late results in the ball flipping gravity off the slope, the predrop has multiple invisible hitboxes, and some of the moving structures in the ending only move visually leaving the layout in place resulting in stuff like the block I clipped next to the orb at 71%. Overall, this level genuinely doesn't feel very fair to play as there are so many issues that any reasonable verifier would have caught onto and fixed after 1-2 practice runs. In no way do I question the verifier's decisions but it really makes me question the legitimacy of its verification due to how many blatant flaws were left in it.

With that being said, this level isn't inherently bad to play, but you do absolutely need some patience during your playtime as the hitboxes take some time to adjust to. It's not the best NC level in its difficulty range but its certainly far from the worst since levels such as Bete Noire and Bausha Vortex are around it, but there are definitely better picks such as FIREPOWER and Molten Core. I would also absolutely recommend playing this with shake off and LDM enabled, I usually use full detail and shake for everything I play but the full detail and shakes of this level obscure the gameplay so much more to the point where the tradeoff in increased difficulty is not even close to worth it here. Overall, I wouldn't recommend this over other levels but if you are a patient player it's not too bad.

Song: Fracture by NightKilla
Attempts: 1,464
Worst Fail: 56%
Enjoyment: 6/10
Extreme Demon #623
Current Placement: Placement Pending
Difficulty Opinion: NLW Remorseless Tier

My Extreme Demon Spreadsheet:
docs.google.com/spreadsheets/d/1yoDFGJ415KP6oy1mdzd4_ompKKWk0yGvq39scneW1D4
Biohazard by Mattsstuff (Extreme Demon)First Victor! Marching Band by Chloe (Extreme Demon)BBBBBBBBBBBBBBBBBBBB by MikeWheelerFan (Extreme Demon)can i have mod now by Devilmine (Extreme Demon)Promethean by EndLevel (Extreme Demon)Mod Level Requests (Demons Only, No Platformers)The Prohibited meat by erzor with @GeckoGD (Extreme Demon)Verification - INTERLOCK by DezonGD & RealStyx with @GeckoGD (Extreme Demon)Canneles au chocolat by AlaskaFX (Extreme Demon)Poltergeist Reborn by ThePrimeEvil (Extreme Demon)The Hell Field by Stormfly (Extreme Demon)Cold Level Go BRRRR by MrSupremeGD (Extreme Demon)
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Biohazard by Mattsstuff (Extreme Demon)

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