User blog comment:Tommy,Klaus&Kol2012+/How to Kill a Levithan/@comment-1509826-20120225013744

I agree its unlikely that the colt could kill them, as there existance was unknown when it was created, I also find it unlikely that any pagan god (maybe kali) could kill them, God oviously could, but its unlikely he will, as for the horsemen, they would probably rip them to scraps with the click of there fingers.

S[ells proably won't work as they are older than them. Nor do I think to much physical damage would work, unless the they ripped them atom by atom. The only thing that I think could really kill them is something as old as they are or older.