[@olcharlieboi] Or use unconventional methods. Such as special powers and magic which he don't have any specific resistance too. 

Quite literally meaning that Humans wouldn't stand a chance unless they have items that can targed his weakness. 
And that Other Monsters would in many cases still be able to fight him unless they completely rely on brute force. In that case they would probably need to beat him to the point where he submit if they intend to defeat him. 



Its mostly because that in near any case I've Ever seen a Demonic creature involved they have 'always' needed a 'special' way to defeat it..... you can't just pick up your pointy stick and stick it until it dies, why?... because its a frikking Demon. There's a reason why demon hunter are invented to stop them, holy water exists and divine artifacts are more than just fancy looking bashers.