Mat block belly drum smeargle is probably broken, especially if it's with a dragonite pivot that's surrounded by es-ate spam/moldy/guts/contrary, hell even unaware.
What about Simple + Geomancy + Cottom Guard Combo? With Stored Power?
Even when you face Unaware pokemon, you still have sick 380 base power move. And other teammates can pass Mold Breaker (Now it didn't work, but if it start work...), and because of nature of PiC, you have absolutly no problem in passing Coverage against Dark Types who wall Stored Power.
With Right invesment you can OHKO Chansey with Eviolite!
However this one... I feel it's not broken, because you need two turns for set-up against Physical oriented teams (and propably also special ones. Some Special oriented pokemon have also better sp. def.) And... Prankser Haze completly destroy this strategy for sure. Unless you have faster Prankster Taunt, but even then you need to predict eatch one will use Haze with Priority.
But why Haze could be even used?
I think Haze will be more popular because of how good Contrary seems to be in this metagame. Physical oriented teams fear double Intimidate, but if you have Contrary on boat, then Intimidate is preety bad against them, especialy when they are Physical oriented, or one is Special when second pokemon - Physical one.
Contrary by itself is really strong ability with right moveset and second Ability into of that. But I'm not scared of double offesnive ability that much, but more Contrary + Defensive ability, like Flash Fire or Thick Fat. Abilities like theese can protect your Contrary user from some moves, what normaly can easly deal with them. Abilities like Magic Bounce, Unaware (Helpfull also for offensive pokemon), Intimidate, Magic Guard (this one is preety good also Offensive ability - makes you immune to Recoil damage from Life Orb, that means your sweaper will live longer and have better chance to survive some moves with your Life Orb on your pokemon)... and much more...
One think what can somehow wall Contrary strategy could be combination of immunities in Grass, Fire, Dragon and Fighting - the key types what gain acces to debuffing effects.
Debuffing moves with theese types: Leaf Storm, Overheat, Draco Meteor, Super Power, Close Combat, V-Create, and from less popular Hammer Arm,
While There is Flash Fire Ghost, and Sap Sipper Fairy type, we can't pass natural immunities into ally pokemon, so Super Power can be used on Fairy type (Who also resist naturaly Fire type), while Draco Meteor - on Ghost pokemon (Who Sadly does not resist Dragon Types).
Second think able to wall this strategy - Unaware. While Unaware Quagsire is not a option because of usualy used Leaf Storm (Because Serperior being that good Contrary user), Clefable is actually good pokemon who can wall Contrary.
Sure, we also need offensive presure on Contrary users, but ability to survive +2 Leaf Storm or Overheat with STAB is viable. Clefable can pass Flamethrower for partner if we don't have Fire pokemon in team, Or Ice Beam if we scared of Flash Fire. Acces to Defensive boosting moves also makes this pokemon even better against this kind of strategy.
Sadly Healing need to be passed from other teammate. Alakazam is good offensive passer - Have Magic Guard AND Recover, also Alakazam can be good user of extra coverage from Clefable.
On another note, Alakazam also resist Fighting type, sadly taking neutral damage from Dragon, Grass and Fire types.
