Rock Core Challenge

Hello, it's Chimplup/SirSkit.
Rock Monotype is really the only type that I've actually become pretty good at, and I encourage other users to try it out sometime. Hyper Offensive Rock teams are really fun to use; it's a shame that Rock is lowest in usage. I guess that's why we have the core challenge though, to get people to try out obscure types, or just any type they haven't used before. Now on to the team!

The Rock core for the challenge was Cradily and Rhyperior. I actually did have a bit of an edge for this challenge, since I had actually used this very same core on my main team :x. I used a physically defensive Cradily to help take on Ground types, since I often needed to preserve Rhyperior at ~100% to counter the major threats, like Metagross or Excadrill. Cradily is pretty good at taking on whatever Rhyperior hates; Water types not named Keldeo, Grass types not named Ferrothorn, and many physical Ground types. Rhyperior pretty much handles any unboosted physical attacker that lack x4 STAB on Rhyperior, particularly the steel types that hard wall Cradily. These two mainly just take hits from faster threats that Terrakion and Diancie-Mega can't overpower, then weaken them enough for Terrakion and Diancie-Mega to spam their destructive STABs. Tyranitar patched up the lack of a specially defensive mon, while not being complete set up bait. If you can get Rhyperior or Cradily under sand, they can take on a surprising amount of special attackers (Rhyperior can just barely take a Landorus-I's earth power). It is also my main answer to Skarmory. Finally, Shuckle is there to take hits and get hazards up reliably. It gives you a MUCH easier time against Fighting, like oml :L Diancie can spam Moonblast once you take out all the sashed mons. Mid-match, Shuckle is usually the mon to sack to get Diancie or Terrakion in safely.

I usually lead with Shuckle to get webs and rocks up asap, unless I see another dedicated hazard lead, like Galvantula. In that situation, I lead with Diancie-mega. It's best to try to mega evolve earlier in the match so you can deter Mew, Skarmory, Sableye, etc, from just spamming their respective hazard or status. I always made sure to preserve Rhyperior if I saw that the opponent had extremely dangerous threat, usually a Steel type. ALWAYS get Rhyperior in safely against these threats (which I'll go into depth about later). Not much else to add here so... here's an importable.
So, here it is, feel free to use it on the ladder or something. The EVs aren't optimal or anything, so you may want to adjust them to something better. I'd recommend keeping Cradily as a physically defensive spread though. I'd prefer if you kept my cruddy nicknames if you do decide to use this team though.

CareToDiancie? (Diancie) @ Diancite
Ability: Clear Body
EVs: 4 Atk / 252 SpA / 252 Spe
Naive Nature
- Moonblast
- Earth Power
- Diamond Storm
- Protect

L-lewdily (Cradily) @ Leftovers
Ability: Storm Drain
EVs: 252 HP / 196 Def / 4 SpA / 56 SpD
Bold Nature
- Giga Drain
- Mirror Coat/Earth Power
- Toxic
- Recover

Fatass 1 (Rhyperior) @ Weakness Policy
Ability: Solid Rock
EVs: 212 HP / 44 Atk / 252 Def
Adamant Nature
- Earthquake
- Stone Edge
- Ice Punch
- Fire Punch

Fatass 2 (Tyranitar) @ Assault Vest
Ability: Sand Stream
EVs: 248 HP / 148 Atk / 8 SpA / 104 SpD
Sassy Nature
- Stone Edge
- Fire Blast
- Ice Beam
- Crunch

Punchachu (Terrakion) @ Choice Band
Ability: Justified
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Close Combat
- Stone Edge
- Earthquake
- Quick Attack

ITS KINDA CUTE (Shuckle) @ Mental Herb
Ability: Sturdy
EVs: 248 HP / 252 Def / 8 SpD
Impish Nature
- Knock Off
- Encore
- Sticky Web
- Stealth Rock

Naturally, Mono Rock teams have quite a bit of threats.
-Mega Metagross - Nothing on this team can OHKO this thing except for Rhyperior's +2 Earthquake (yes, +2 only). It's crucial to get Rhyperior in on a free switch to counter this monster. If it packs Grass Knot, there really is not a good answer to deal with it. Although, I've found that most Grass Knot Metagross usually lack Bullet Punch, so you might be able to win a speed tie and hit it with Diancie's Earth Power.
-Excadrill - Another huge threat that is dealt with by Rhyperior, Excadrill causes you to sack something to get Rhyperior in safely. This becomes a bit more frustrating if the opponent is smart and doesn't try to take on Rhyperior with Excadrill.
-Azumarill - Belly Drum sets are especially dangerous, since +6 obviously cleanly OHKOs most of the team. These sets also outspeed Cradily and OHKO, but Non-BD aren't too bad to deal with. If you don't know which set Azumarill is running, it's best to assume bellyjet on Fairy and Sap Sipper/Band on Water. If you believe that it is BellyJet, make sure to deal the most damage possible, or just use Encore with Shuckle. At that point, you need to whittle down Azumarill by sacking Tyranitar and activating sand, then play around with switching. At ~20%, Terrakion can OHKO with Quick Attack.
-Fairies - Some are plain just too bulky for Terrakion/Diancie-Mega, especially with screens up. My only special wall is very vulnerable to fairies, so most of the time you need to get sand up, hard switch into Cradily, and hope to nab a threat with a surprise mirror coat. Gardevoir-Mega is a huge pain sometimes, but Terrakion can revenge it decently. Diancie-Mega, especially CM variants, give me tons of trouble. You can try to use Mirror Coat like I said above, tank then OHKO with Rhyperior under sand, or try to win the speed tie with your own Mega Diancie.
-Fast Water types - Not exactly swift swimmers, since Cradily can deal with some of the more common SS mons. Keldeo and Greninja however, cause a bit more trouble. Try to get Shuckle's webs up asap to be able to revenge these things with Mega Diancie and Terrakion. Outside of webs, Mega Diancie can revenge Specs Keldeo, and Terrakion can OHKO Keldeo with close combat (although you need to win the speed tie).