#2 Rey Mysterio
Another great match for WWE's Saudi Arabia show would be Rey Mysterio vs. The Undertaker, as the two have worked well together in the past. On top of that, one would assume that Mysterio is able to have a good match with just about anyone on the roster, even someone as limited as the legendary "Phenom."
If Mysterio ends up winning the United States Championship at WrestleMania, which doesn't seem likely, then the match could be spiced up by being a US Title match, although it'd be strange to see the ageing legend challenge for a secondary title at this point in his career.
It's more likely that, if this is the planned match for the May 3 Saudi Arabia show, Rey Mysterio will lose his US Championship match against Samoa Joe at this coming Sunday's WrestleMania, thus ensuring that his potential match against The Undertaker will be a non-title showcase.