I never say "I'll never take x seriously again" because to me that's a load of bs (Uh, Jinder won, the WWE Championship will never have prestige again. Uh, Roman won, I'll never watch him vs Brock. Uh, something I didn't like happened, I'll never do something we all know I'm going to do. Ect.) but if Taker does return, I really will never take retirements in WWE seriously again. This isn't Mark Henry pretending to retire, this is the number one WWE star possibly ever and Vince McMahon's personal favorite. They put in all the work for a great goodbye, put together great video packages, did great promos, ect. If they do all of that for a match with no steam whatsoever, just John Cena wanted some match and the Undertaker replied "Sure bro, I got you." then it's all for nothing. Match over, goodbye Undertaker, wait, no, he'll be back for WM 35. Then, WM 36. Why not WM 37 after, let's make him the new Terry Funk. I get it, rumors have been circulating, Cena called him out, fans want to see it, but it's too late. It's like if in Sherlock Holmes they kill Watson, dedicate an episode to his death, then bring him back the episode after that.
Tldr- Rey all the way