As was previously reported, there is some talk going on backstage in WWE about possibly having The Undertaker wrestle a match against current WWE World Champion A.J. Styles at some point within the coming months.
According to Dave Meltzer of The Wrestling Observer Newsletter, there is a decent chance that we may see this happen at the 2017 Royal Rumble pay-per-view. Meltzer said the following:
"There has been legit talk of doing A.J. Styles vs. Undertaker at Royal Rumble. We haven’t heard that it’s a done deal, but it is something talked about. If Undertaker was to win, they could have Cena go for No. 16 against Undertaker at Mania, since Cena vs. Undertaker is a match never done before at Mania. There may be a timing issue since Undertaker had recent hip surgery and is going through rehab right now."