Revenankh was a Pokemon made to be the perfect Bulk Up user, and while it might have taken a hit in viability due to the addition of the Fairy type, it is still one of the best users of the move. Revenankh's excellent Ghost / Fighting STAB combination allows it to hit the entire metagame for at least neutral damage, allowing it to forgo coverage moves. Revenankh's decent base 105 Attack isn't the most ground-shaking, but it is more than enough for a Bulk Up user. It also has great natural bulk of 90 /90 /110, and that in combination with reliable recovery and STAB Drain Punch allows Revenankh to tank most neutral hits, greatly contributing to its ability to set up. Revenankh also has a fantastic ability in Shed Skin, which allows it to shrug off damaging status such as poison or burn, and reliably set up in the face of Scald. Ghost / Fighting is a decent defensive typing, as it gives Revenankh an immunity to Normal- and Fighting-type moves and neutrality to Knock Off, which makes it one of the few Pokemon able to spinblock Colossoil reliably.
While Revenankh is a phenomenal Bulk Up user, its low Speed and average starting Attack stat mean its Bulk Up set is by far its best set, and as a result, it is predictable. Shadow Sneak is necessary for it to strike first, and without several boosts under its belt, it can be underwhelming. Revenankh's typing also leaves it weak to Fairy- and Flying-type moves, two types that are very common in the metagame, and its reliance on Bulk Up to deal damage leaves it walled by Unaware users, most notably Clefable.
Bulk Up will allow Revenankh to set up on physical attackers, and after several boosts it can deal heavy damage to most Pokemon. Drain Punch is Revenankh's best Fighting-type STAB move, as it has decent Base Power and helps prolong Revenankh's longevity by recovering HP. Shadow Sneak is the recommended secondary STAB attack, as it achieves perfect neutral coverage with Drain Punch and is necessary to hit faster threats first. It can be used to get that last bit of damage on a sweeper such as Aurumoth, but it won't be doing any major damage without a couple boosts. The last moveslot is used either for healing or additional coverage; reliable recovery helps with setting up, whereas additional coverage lets Revenankh get past its would-be checks reliably. Moonlight is preferred, as it provides Revenankh with a reliable source of recovery, but Rest can also be used, as it has more PP and heals more HP. The two potential turns lost can leave Revenankh susceptible to being worn down by powerful attackers, but Shed Skin can help mitigate this. Earthquake is also an option, as it allows Revenankh to beat Mollux and Plasmanta, which can otherwise be difficult for Revenankh to beat. Ice Punch allows Revenankh to beat Tomohawk lacking Taunt or Haze, as well as deal heavy damage to Mega Altaria.
The given EVs and nature give Revenankh the highest possible special bulk, because Revenankh can boost its Defense by itself. The spread also allows Revenankh to act as a reliable check to special attackers such as Syclant and Levitate Stratagem, especially when running a recovery move to heal off the damage it'll take in the process. Leftovers gives Revenankh passive recovery and is very important for sets running a third attack. Shed Skin is the best ability for this set, as it allows Revenankh to shrug off status with a little luck, letting Revenankh set up in the face of Toxic and Scald users. This is especially helpful versus passive walls, such as Chansey, and also allows Revenankh to sometimes wake up early from Rest sleep.
Revenankh does not have the stats to deal heavy hits without boosting, so try to boost up as much as possible without leaving Revenankh vulnerable to being knocked out. Revenankh is fully capable of 2HKOing or OHKOing Pokemon after several boosts. The boosts are also vital in preventing Revenankh from being revenge killed by physical attackers. As Revenankh's main use is as a win condition, it is vital that you weaken or KO the foes that can stop it, mainly Fairy-types, Tomohawk, and phazers, or else any attempt at sweeping will be stopped short. The ideal Pokemon for Revenankh to set up on are either passive walls, such as Chansey, or physical attackers that cannot hit it super effectively or boost up alongside it, such as Landorus-T, Mega Sharpedo, and Mega Beedrill.
Stealth Rock support is much-appreciated, as it helps wear down the Flying-types that can check Revenankh. Pyroak can set up Stealth Rock and is able to beat or at least wall most Fairy-types, and while they do stack a Flying weakness, Revenankh can reliably check some Stratagem and other Rock-types that threaten Pyroak. Steel-types also make for good teammates, as they are generally able to take the Fairy- and Flying-type attacks aimed at Revenankh, and in return Revenankh can take the Fighting-type attacks aimed at them. Heatran, Ferrothorn, and Scizor all make for notable teammates, as the first two can reliably set up Stealth Rock while all three can punish Fairy-types. Pokemon that can reliably remove Tomohawk are essential, as it can put a hard stop to Revenankh, so Fairy-types make good for teammates. Clefable in particular can set up Stealth Rock and beat opposing setup sweepers by virtue of Unaware. Pokemon that can handle Flying-type spam, such as Cyclohm, Skarmory, and Plasmanta, make for good partners as well, especially because Cawmodore and Talonflame can use Revenankh as setup bait if it is lacks a Bulk Up boost. Colossoil, along with other Dark-types, can be used to help alleviate Revenankh's Psychic weakness, but they stack a Fairy-type weakness and Revenankh can beat most Psychic-types itself after several boosts.
Drain Punch allows Revenankh to take advantage of its bulk by regaining HP; it OHKOes many common threats such as Colossoil and Stratagem and can even 2HKO defensive Pokemon like Chansey and Ferrothorn. Shadow Sneak's Ghost typing provides useful coverage when combined with Drain Punch and allows Revenankh to check many threats such as Mega Gardevoir, which it can OHKO after Stealth Rock damage; Aurumoth, which takes over 50% damage; Gengar, which it OHKOes; and Latios, which takes almost 90% damage. It also allows Revenankh to pick off weakened threats or frailer Pokemon. For example, it can be used as a stop to Mega Alakazam, Kerfluffle, many weakened setup sweepers like Manaphy and Serperior, and Pokemon with a broken Focus Sash. Ice Punch helps Revenankh overcome defensive Ground-type Pokemon like Gliscor, Landorus-T, and Garchomp, and it deals more damage to Flying-type Pokemon like Thundurus and Dragonite and Grass-type Pokemon like Serperior. It is also the most powerful option against Tomohawk and can OHKO Tornadus-T. Alternatively, Earthquake makes Revenankh a much better check to Mega Crucibelle, especially Coil variants that it would otherwise struggle against. It also lets it deal more damage to Electric-type threats like Krilowatt, Cyclohm, and Raikou, and it OHKOes specially defensive Heatran, which Drain Punch is not guaranteed to do, as well as Mollux. Another option is Power Whip, which deals with bulky Water- and Ground-type Pokemon well, OHKOing Politoed, Mega Swampert, Manaphy, Quagsire, and Krilowatt, as well as 2HKOing Hippowdon, Rotom-W, Slowbro, and +1 Arghonaut. Another option to consider is Rock Slide, which OHKOes Mega Charizard Y, Charizard, Talonflame, and Volcarona, which is useful for predicting a switch, and it can also potentially OHKO Tornadus-T. In the fourth slot, Trick allows Revenankh to give its Choice Band to the foe, letting it use all of its moves freely while burdening the foe with the item. It is best used on hard counters to Bulk Up Revenankh, such Haze Tomohawk and Unaware Clefable, to greatly diminish their utility and longevity; it can also be used on special attackers to make them useless and force them out. However, be wary of Tricking a Choice Band onto a Pokemon that can benefit from it, such as physical attackers. Moreover, using Trick when a Mega Pokemon switches in gives it a free turn.
248 HP EVs increase Revenankh's longevity while allowing it to switch into Stealth Rock one extra time. Maximum Attack EVs allow Revenankh to deal maximum damage, and Adamant is the preferred nature so that Revenankh can attack with more power. Choice Band allows Revenankh to deal as much damage as possible and potentially burden the foe with Trick. Air Lock allows Revenankh to perform better against weather teams, especially rain and sun, allowing it to take more hits against them and potentially outlast Pokemon on the former with Drain Punch. For example, Drain Punch is a potential 2HKO on Mega Swampert, and Mega Swampert's Earthquake can do about 66.5%. However, Waterfall does a minimum of that in rain.
Teammates also appreciate being more resistant to common weather users, such as Mega Charizard Y and Swift Swim Pokemon. Shed Skin is still a viable option, though, but it is unnecessary because this set is based on attacking as opposed to setting up and surviving for a long time. Nevertheless, it can help Revenankh switch into Chansey, Ferrothorn, and Heatran if it is poisoned, paralyzed, or burned, although it isn't the most reliable option.
Revenankh is most useful early- and mid-game. Focus on using it to cripple or remove walls with its offensive moves or Trick, making it easier for its teammates to take out the opposing team without the worry of being hard countered. Shadow Sneak can be used to check a faster foe that may be on a path to sweep your team. If you are predicting the opponent to switch to a specially oriented check or counter, use Trick to force it into a move. For example, if your opponent currently has Mega Crucibelle out against your Revenankh but has a cleric Clefable, there is a fair chance of that Clefable being sent out, in which case Revenankh can use Trick and force its Choice Band on the Clefable, making it a less effective cleric while Revenankh gets the useful Leftovers.
Setup sweepers such as Manaphy and Aurumoth are perfect teammates for Choice Band Revenankh because of its ability to support them by removing Pokemon that stop them from setting up, such as Chansey and Ferrothorn. Pokemon like Cawmodore and Mega Altaria appreciate Haze Tomohawk, Klefki, and Clefable being crippled by Trick. Choice Scarf Mollux, Choice Scarf Volkraken, and Talonflame are able to counter or check Cawmodore, which uses Revenankh as setup bait. In return, Revenankh removes walls like Chansey and Ice Punch Garchomp. Mollux appreciates Revenankh's ability to handle Colossoil, Crucibelle, Stratagem, and Tyranitar. Finally, Ice-type Pokemon such as Kyurem-B and Weavile can help Revenankh by beating Flying-types like Tornadus-T and Tomohawk.
Shadow Punch or Hammer Arm can be used for their higher Base Power but are generally inferior to Drain Punch and Shadow Sneak as they lack both recovery and priority. Knock Off has redundant coverage with Shadow Sneak, but it can remove items such as Eviolite and Leftovers. It's worth noting that the biggest user of Eviolite, Chansey, and the biggest user of Assault Vest, Colossoil, are already hit super effectively by Revenank's Fighting-type STAB move. Taunt or Glare can be used in the last moveslot as well, but does not offer much in terms of supporting Bulk Up. Taunt can be used to better set up on walls or to prevent phazing, but considering that it requires either dropping a STAB move or recovery, it is a niche option. Glare can be useful for shoring up Revenankh's poor Speed and crippling switch-ins, but has no use aside from that. Toxic can be run in the last slot to cripple some switch-ins but it has no use otherwise. A physically defensive spread of 252 HP / 4 Atk / 252 Def can be used to allow Revenankh to switch into Colossoil with impunity, but this is only ever necessary on teams that need a reliable spinblocker to Colossoil, namely Sticky Web teams.
Checks and Counters
Unaware: Unaware users, the most prominent being Clefable, are the most reliable checks to Revenankh. Quagsire and Arghonaut fear nothing short of Power Whip from Revenankh, and Clefable can hard counter Revenankh completely.
Fairy-types: Fairy-types are almost impossible for Revenankh to beat, as most, such as Mega Altaria, Mega Diancie, and Sylveon, can take a +6 Shadow Sneak and either KO or deal heavy damage to Revenankh. Mega Gardevoir can tank a +2 Shadow Sneak from full health and OHKO Revenankh with Hyper Voice, but it will take a large amount of damage in the process. Clefable can completely counter Revenankh by virtue of its good bulk and Unaware.
Flying-types: Flying-types such as Mega Pinsir and Talonflame can threaten Revenankh out with their powerful STAB moves, and Revenankh requires many Bulk Up boosts on to even consider beating them. Tomohawk can completely counter Revenankh if it runs Haze, negating any Bulk Up boosts Revenankh had accumulated. Even if Tomohawk lacks Haze, Revenankh will need to boost many times to beat it, and because Air Slash is a clean 3HKO, Revenankh will be under heavy pressure to do so. Offensive Tomohawk sets will also cleanly OHKO Revenankh with a Life Orb-boosted Hurricane.
Stat Boost Removal: Haze and Clear Smog can completely reset Revenankh's boosts, preventing it from sweeping and taking away most of the pressure it can put on a team. The most effective users would be Tomohawk and Quagsire, which can already wall Revenankh. Amoonguss can also stop Revenakh variants that don't run a third attacking move, as can Plasmanta.
Phazing: Phazing moves can stop a Revenankh sweep short, and Pokemon with high Defense, such as Skarmory, Cyclohm, and Pyroak, can reliably use them, although they will have take heavy damage from a fully boosted Revenankh, and they fail outright if Revenankh carries Taunt.
Powerful Special Attackers: Pokemon that can take a Shadow Sneak and hit hard, such as Mega Charizard Y, Tornadus-T, and Mega Pidgeot, will be able to severely damage Revenankh with super effective or powerful STAB attacks, but they must be wary of Revenankh when it has accumulated multiple boosts.