3. Kane
WWE.comAs Triple H's current demon henchman, Kane is still regarded as one of the top heels in WWE. There is only one real theory as to why you would match Sting up with the demon, and that is clearly due to the link with the Undertaker. Although Kane is a definitive heel right now, he has always shown some sort of morality towards his half-brother. So, would Sting have to go through Kane to get to Undertaker? It's a real possibility, especially with Taker still sidelined after his collapse backstage at Wrestlemania 30. This match would serve as a good filler for Sting, who can work off some of his ring rust, whilst still building towards that dream match with the Undertaker. Kane's current heat is another thing that will work well with Sting, who will be coming into the company as a babyface. The WWE need to put someone against him who can hold their own whilst preserving themselves as a legitimate challenger. Kane can be that man. Kane is one of the more possible feuds should Sting debut on WWE TV. His link to Undertaker is extremely important to why this would work, and is a viable rivalry to help give Sting some momentum.