Okay, first of all, I have to thank
AM for this. I'm not entirely sure why this hasn't been brought up, but it's excellent, nonetheless.
SpDef M-Gardevoir.
So far the set I've been using (I'm sure it could be optimized, but w/e) is this…
Gardevoir @Gardevoirite
Calm Nature
EVs: 248 HP/252 SpDef/8 SpA
-Wish
-Protect
-Will-o-Wisp
-Hyper Voice
This thing is so beautiful, especially against all the M-Sableyes running amok in the tier. People get so wrapped up in that base 165 SpA that they forget the 135 SpDef it has. This thing has a LOT of special bulk. I've only loosely built a team around it, but it's put in work in the 2 games I've played, so I suspect that won't really change much. It fits perfectly on teams with Heatran, seeing as Heatran quad resists Steel, is immune to Poison, and can tank pretty much any Ghost move in the tier. WoW is great for surprising Scizors/Bisharps that think they can counter/check you. I guess you could slash Heal bell over WoW, but I like punishing things permanently. WishTect for recovery/team support. Hyper Voice murders souls. Even with the EV spread above, you still hit a staggering 368 SpA. That means you can still hit like a truck.
I'll edit in replays when I ladder up to a respectable spot, but this thing looks like it'll be an awesome addition to our repertoire.