#2. Feud with Elias
John Cena could claim that he wasn't fully prepared for the match because Elias came out and surprised him when he called out The Undertaker. It would be interesting to see if Cena blames Elias for the fact that he was defeated last night and this could then open up a feud between The Drifter and John Cena moving forward.
It's something that has been teased in the last few months, but it would be interesting to see how much Elias could learn from Cena through a feud that could then lead to something much bigger.