#1 The Undertaker and Sting

This dream match, between The Undertaker and Sting, has been teased by WWE and Sting for months, and we hope that it happens, with the seeds to the feud set at the RAW reunion show.
Sting or The Undertaker haven't been advertised for the RAW reunion show, but WWE could maybe make that announcement in the days to come.
From WWE's social media handle teasing a possible match between the two, Sting talking about how he would return for one last match to face The Undertaker, as well as other hints that WWE have dropped, this is a dream match that could be a reality.
A PPV like SummerSlam needs a big match, which could very well be this one between these two greats of the pro wrestling industry. Sting's last match was back in 2015, when he faced Seth Rollins at Night of Champions, while The Undertaker's was much more recent, a week ago at Extreme Rules, when he teamed up with Roman Reigns to face Shane McMahon and Drew McIntyre.