Webfirstly, muzan needs to enhance them all with the maximum amount of blood they can withstand to be as strong as possible. Lure yoriichi to the infinity castle, either. Webif muzan saw any upper moon becoming strong enough to defeat him he probably would either kill him/her or manipulate them via his blood cause as we know he has control. Webin the dark world of demon slayer, the upper moons strike much fear into the hearts of both humans and demons. These fearsome foes in the series are the elite. Webthese powers come directly from the twelve kizuki’s blood relationship with muzan. You can think of blood demon arts as a countermeasure against demon slayer. She is one of japan’s top demons and a force to be reckoned with. She is the primary antagonist of the entertainment district. Webalthough daki is the first to be introduced in the ‘entertainment district’ arc, gyutaro is acknowledged as the true upper rank 6 demon by muzan himself. Webif the upper moons were all pillars against a weakened muzan like the one the pillars fought, they stomp him. Assuming muzan can't auto kill him they can stall him to daytime easily. The injured pillars were able to do this (albeit just barely).
