i have an idea!

So, everyone has the same pertanyaan on there mind, right? How the crap are they going to kill the freaking devil if the kuda jantan muda, colt wont work?!?!!!! well, ive heard some interesting theories like, Cass will kill him atau dean will give in atau they find some anciant latin spell to send him back to hell.
Well, im here to share my idea inwich i would like anda to consider:what about the little boy? ya, know, the one that left for Australia atau somewhere and is half demon and half human(i so want a cas action figure!). i think hes going to tampil up and somehow kill lucifer. but its just an idea. how they contact him and why the kid will help is beyond me. but as soon as i think of sothing else, i will let anda know. what do anda think?