If only Catcher didnt exist. And it could use Crystal Wall instead of Crystal Edge.
As is, maybe with Emboar? If the opponent can't OHKO you, you can:
1st, hit their active ex for 100
2nd, let them attack your WKex for whatever
3rd, catcher up one of their undamaged exes for the OHKO
4th, let them kill your damaged WKex
5th, kill that ex you damaged earlier.
Now you'd essentially have the game on lockdown if they can't OHKO your WRex.
[del]But Catcher is a thing so this wouldn't work as well as I wish it would.[/del] Actually nevermind. Works better with catcher.
You could even run Reshiram/Moltres to beat the heck out of annoying Klingklang/Safeguard dudes.