Tyranitar will earthquake off the bat all the time now, cause if that comes in on crunch and uses rock polish, you'd better hope you have scizor, breloom and/or azumarill on your team. Even then, you have to hope it's used close combat or has already suffered life orb recoil.
Thank God I always run Scizor. And Superpower Tyranitar. But this thing would be a great addition against said users as well.
This thing will do so much damage after switching in on a Dark type move and Swords Dancing up.