User blog comment:Twilight Despair 5/Abaddon as the Season 9 Big Bad?/@comment-82.34.210.166-20130519043503

Abbadon has to  be vulnerable to the demon bomb, so could yet be killed. As the last known knight of hell, it is the best option as ruler of hell. Crowley will fight tooth and claw for his life and power, as well as to stop the cage being opened.

Crowley did have access to the lucifer crypts, and as demon king access to alot of stuff, so could make an epic fight. The thing is the only thing he has to fight abbadon that is known to work is the angel blade, but as it is a knight of hell, may not be certain. Does crowley even know how to make a demon bomb? Seeing as it took archangel to deal with just 12 knights, crowley needs the winchestors to back him up.