This, but it's not that simple.
I like to set up at least 1 eel on the bench to recycle milled lightning energy, and have a free retreater on the bench just to give myself some options WHEN (not if) my zekrom gets KOed. 2 zekrom is staple because you're always expecting your first zekrom to be KO'd, either by cobalion, rotom, or black belt + durant. Switches/junk arms/and DCE are the most important cards in your deck at this point.
Also, if you can get a 40hp tynamo to start with, you can use its attack to paralyze durants, potentially saving you a few turns while you're trying to set up the field I described above.