Rhyperior's biggest problem is the competition it faces for a team slot. Although it possesses greater defensive stats than any of its fellow Ground-types, its lack of instant recovery is a letdown, something Gliscor and Hippowdon both have access to. Swampert's offensive and defensive stats seem poor compared to Rhyperior, but the mudfish has superior defensive typing and can use special attacks effectively.
When considering Rhyperior for a slot as an offensive Pokémon, its low Speed means it requires support to effectively use Swords Dance to sweep with. Metagross provides stiff competition for the Rock Polish variants because it is able to reach much higher speeds and employ Explosion if necessary to get a team member in for free.
However, this does not take away from the fact that Rhyperior is a very powerful Pokémon. 434 HP and 394 Defense are very hard to break when paired with Solid Rock and the potential for a free Special Defense buff from a sandstorm. Rhyperior is not to be underestimated and is a good choice on most teams if you can play to its strengths.
In short, using Rhyperior is akin to making a pact with the devil: you gain incredible amounts of physical power. This can let you 2HKO anything in the metagame with a Choice Band, and the potential to boost your offensive prowess further with Swords Dance or Rock Polish is tempting. However, you should be ready to pay the price in accruing a painful weakness to the ever-so-common Scizor, Gyarados, and Starmie. Rhyperior is not the kind of Pokémon you can simply throw on a team and expect to succeed. It needs a good deal of support to truly shine.
Rhyperior has one of the highest Attack stats in the game combined with two extremely useful STABs. Not many things will enjoy taking an Earthquake or Stone Edge from 624 Attack. The attacking combination of Ground and Rock is only resisted by a handful of Pokémon in OU, including Bronzong, Breloom, and Flygon. The remaining two slots are used to deal with these Pokémon. Aqua Tail deals a minimum of 59% damage to 252 HP / 252 Def Impish Hippowdon, a guaranteed 2HKO even when factoring in Leftovers recovery. Megahorn is Rhyperior's best option against enemy Celebi, easily OHKOing even the most defensive variants. Fire Punch allows Rhyperior to net a guaranteed 2HKO against 252 HP / 80 Def Sassy Bronzong.
Maximum Attack EVs are a given on a Pokémon with such an astoundingly high Attack stat. 252 Spe EVs allow Rhyperior to reach a stat of 177, just outspeeding Skarmory that sit at a stat of 176. Rhyperior is now able to 2HKO Skarmory with a Stone Edge before it has the chance to shed its Flying-type with Roost. As an alternative, Rhyperior can run 192 HP / 100 Atk / 156 SpD / 60 Spe in order to always survive 236 SpA Grass Knot from Celebi and 405 Attack Meteor Mash from Metagross. It is recommended that you run both Megahorn and Fire Punch when using this defensive spread.Team Options & Additional Comments >>>
Rock Polish solves the problem of Rhyperior's abysmal Speed. With max Attack and Life Orb, Rhyperior will be firing off attacks with an Attack stat of roughly 492. Earthquake and Stone Edge give the set the basis of its coverage, while the fourth moveslot is used to cover specific threats. Aqua Tail seriously dents Claydol and Hippowdon while Megahorn quickly disposes of Celebi. Substitute can be used in tandem with Rock Polish in order to protect Rhyperior from status and aid in getting a boost off successfully. On this set, Fire Punch lacks the raw power to successfully deal with Bronzong, so Fire Punch is not used.
With a Jolly nature and 252 Speed EVs, Rhyperior reaches a Speed stat of 196. Therefore, Rhyperior's Speed stat is 392 after a single Rock Polish. An Adamant nature can be used, but Rhyperior will outspeed Gengar at most, losing to Starmie, an opponent that is relatively vital to outspeed.Team Options & Additional Comments >>>
A Pokémon such as Rhyperior is an excellent candidate for Swords Dance. Being aided by its somewhat impressive defensive capabilities, its massive Attack stat, and very powerful STAB attacks make Rhyperior perfect for this type of set, if it wasn't for his Speed. Thankfully max Speed is adequate to outpace most Skarmory, so using Stone Edge will be of little concern for Rhyperior. Speaking of Stone Edge, following a Swords Dance it OHKOes Gliscor if Rhyperior is using an Adamant nature; a true feat for this set. Earthquake deals massive damage even to Hippowdon, doing roughly 85% damage on average. Megahorn is an excellent choice because it 2HKOes Bronzong. Fire Punch is capable of beating down Bronzong; however, that will be the only time it will be useful.Team Options & Additional Comments >>>
Rhyperior's ability to conjure 101 HP Substitutes, the ability Solid Rock cutting super effective moves to 1.5x damage instead of 2x, and the 1.5x boost to his Special Defense thanks to the presence of sandstorm make this Rhyperior a potent threat when played correctly. Substitute is the key move on this set. With the given EVs, Blissey is not able to break Rhyperior's 101 Substitutes with Seismic Toss. Cresselia also suffers this same scenario, provided she didn't get a Special Attack boost from Charge Beam or has Psychic in her move pool to obtain a Special Defense drop. After the Substitute is set up, Rhyperior can act accordingly by either boosting its 400 Attack stat to an impressive 800 with Swords Dance or simply using its powerful STABs to attack.
The Speed EVs outpace minimum Speed neutral-natured Swampert. Don't worry about being walled by Bronzong because Gyro Ball is doing pitiful damage and after a couple of Swords Dances even Bronzong won't enjoy a boosted Stone Edge. If Celebi and other bulky Psychic-types become a problem, Megahorn fits nicely over Swords Dance.Team Options & Additional Comments >>>
The idea is pretty simple—switch into physical attackers with Rhyperior's amazing defenses and strike back with 316 Attack and great STAB moves. Megahorn provides coverage against Grass-types and makes a big dent in Cresselia and Celebi, while Avalanche hits Gliscor hard and can also bring down a Dragon Dancing Dragonite, if you don't want to rely on Stone Edge's shaky accuracy. Stealth Rock is always useful due to its ability to shave off a portion of any opponent's HP. Roar helps phaze Dragon Dancing Dragonite and other possible threats.Team Options & Additional Comments >>>
This set is similar to the above set, but now Rhyperior has recovery in the form of RestTalk. Rest allows Rhyperior to snooze away any damage it has taken during the course of the battle while removing any hindering status effects. Sleep Talk allows Rhyperior to continue attacking even while asleep. However, Rhyperior is not the most effective absorber of sleep, due to the opponents who commonly use the status, such as Gengar, Breloom, and Roserade. The specifications of the EVs are mentioned in the above set's comments.Team Options & Additional Comments >>>
Rock Blast can be used to break Substitutes and destroys any Ninjask that dare to try and set up on Rhyperior. Rock Slide can be used over Stone Edge if the low PP and accuracy concern you, although the flinch rate is of no real consequence on anything but the Rock Polish set. Focus Punch isn't generally much use due to a STAB Earthquake or Stone Edge having the same power and Fire Punch being just as powerful against Bronzong. Toxic works decently on the more defensive sets if bulky Water-types such as Vaporeon prove to be a large problem. Counter can be used to launch back things such as Flygon's Earthquake and unboosted Gyarados' Waterfall. Endeavor can work on the Rock Polish set if you are low on health. The only thing to say about Rhyperior's signature attack, Rock Wrecker, is that it shouldn't be used.
Checks and Counters
Barring boosted Megahorns and Focus Punches, Bronzong can shake off pretty much anything Rhyperior can throw its way and hit back with Grass Knot. Skarmory can't hurt Rhyperior, but can stall Rhyperior out—especially the Choice Band set—provided it is faster by wasting Stone Edge's PP with Roost and simply Whirlwinding Rhyperior away.
Swampert handles Rhyperior decently and can bring him down with STAB Water attacks. Surf and Hydro Pump are more effective than Waterfall because they hit the weaker of Rhyperior's defensive stats. Suicune also fares well if it can avoid a critical hit from Stone Edge. Hippowdon can wear Rhyperior down by alternating between Earthquake and Slack Off. Beware of Choice Banded or Swords Danced Avalanches or Aqua Tails though.
If you can get them in on either of Rhyperior's STAB moves, Breloom and Torterra handle Rhyperior well. Both can fire off Seed Bomb, while the latter can also use the more powerful Wood Hammer. Flygon can also work somewhat, although like the previously mentioned Grass-types, be sure to avoid Ice attacks and repeated hits from Megahorn. Defensive Celebi also works well as a counter; however, it must avoid a predicted Megahorn. STAB Grass Knot, with 120 Base Power due to Rhyperior's girth, will OHKO the rocky beast as long as Rhyperior does not invest heavily in Special Defense and a sandstorm is not raging.