Rotom-C is most commonly seen using a Choice Scarf, and for good reason. It has just about everything you could ever ask for in a Choice Scarf user. It has a great base 105 Special Attack, solid base 86 Speed that lets it outspeed most unboosted threats and even some boosted threats, a good set of resistances to switch in easily, and a momentum grabbing attack in Volt Switch.

Volt Switch is what makes this set amazing. Even if it's prepared for, Rotom-C can simply use Volt Switch early on to scout how the opponent intends on playing against it. Leaf Storm is Rotom-C's signature move and it also crushes virtually any Pokemon trying to block Volt Switch, including Rhydon, Golurk, Lanturn, and Manectric. However, you must take caution in utilizing Leaf Storm, as the resulting Special Attack drop will make Rotom-C setup bait for many dangerous sweepers. With Thunderbolt, Rotom-C becomes one of the hardest late-game cleaners to stop in RU, as its combination of Speed and power will be too much for any team that has had its checks and counters weakened or KOed over the course of the match. Despite this, Hidden Power Fire is still a worthy option. With it, Rotom-C gains the ability to effectively revenge kill Sceptile and Durant—both of which are very dangerous attackers in RU—in a moment's notice. Hidden Power Fire also prevents Ferroseed from walling Rotom-C. With Trick, Rotom-C is able to cripple walls such as Ferroseed and Clefable, two Pokemon that prevent Rotom-C from revenge killing its targets. With an important wall crippled by Trick, Rotom-C's teammates will find it much easier to execute their sweeps.

A Timid nature is used so Rotom-C is able to outspeed as many threats as possible. Rotom-C can't risk running a Modest nature, as it is then outsped by boosted positive base 80s such as Medicham, Braviary, and Kabutops.

Like with any other Choice Scarf user, Rotom-C appreciates entry hazard support. Smeargle, Accelgor, Scolipede, and Qwilfish can all set up various forms of entry hazards. The first three are seen on more offensive teams while Qwilfish is seen on more balanced teams. Qwilfish also has surprisingly good defensive synergy with Rotom-C. After Rotom-C uses Leaf Storm, it is often forced out by Fire-types such as Entei and Emboar, so Qwilfish makes for a solid switch-in to these two threats in particular. Although Volt Switch and Thunderbolt can dent them, a check to Fire-types is still advised so Rotom-C can use Leaf Storm more freely. Slowking, Lanturn, and Poliwrath work as solid partners for the same reason as Qwilfish. Grass-types in general give Rotom-C trouble, as it will be unable to do much of anything to them without Hidden Power Fire. Fire-types such as Entei, Emboar, and Typhlosion may be enemies to Rotom-C, but they are also great partners for it, as they are solid answers to most Grass-types in the tier. The first two can even deal with sleep thanks to Sleep Talk, while Typhlosion has a powerful Choice Specs Eruption that can quickly weaken an opposing team for Rotom-C to clean up. Like with any other Volt Switch user, Rotom-C works well on VoltTurn teams, so Pokemon that can utilize Volt Switch or U-turn, such as Braviary, Manectric, and Mesprit, can all work nicely with Rotom-C.

When donning a pair of Choice Specs, Rotom-C becomes one of the tier's most powerful wallbreakers. This Rotom-C is particularly effective against more balanced teams thanks to its immediate power, solid resistances, and good Speed.

Rotom-C seems outclassed by the likes of Typhlosion and Slowking, but it has one major move over them: Volt Switch. With a Choice Specs boost, Volt Switch hits much harder than you might originally think, and can give many opponents quite the surprise. Leaf Storm is just brutal on this set; virtually anything without a resistance to the move is 2HKOed at worst. Even some Pokemon that resist the move can be dealt with after Stealth Rock. Sceptile and Tangrowth are 2HKOed with Stealth Rock support alone while Galvantula gets OHKOed under the same conditions. Furthermore, Leaf Storm still hits relatively hard after the Special Attack drop on this set. That said, bulkier setup sweepers such as Gallade can still effectively set up after the Special Attack drop from Leaf Storm. Thunderbolt is preferred in the third slot to give Rotom-C a reliable STAB option to use as it has no drawbacks. Assuming a Modest nature, it also OHKOes Entei and Typhlosion and has an 87.5% chance to OHKO 4/0 Emboar after Stealth Rock. In spite of this, Hidden Power Fire is a viable option on this set. With the power boost from Choice Specs, Hidden Power Fire allows Rotom-C to run through the likes of Escavalier, Steelix, and Ferroseed. In the last slot, Trick is the main option as it lets Rotom-C cripple various walls for the remainder of the match. However, if you want both Thunderbolt and Hidden Power Fire, Trick can be eschewed to get the best of both worlds.

As Choice Specs Rotom-C relies more on its power rather than its Speed, 208 Speed EVs are used to get the jump on base 80 Speed Pokemon. The remaining 48 HP EVs improve Rotom-C's overall bulk. The nature choice is also a fairly tough one, as both have their merits. With a Modest nature, Rotom-C gets a sizable power boost that lets it break down most Fire-types with Stealth Rock support alone, cutting down on its dependency on its teammates to help it with them. However, because Kabutops, Mesprit, and Braviary sometimes use positive Speed natures, Timid can be used to ensure Rotom-C outspeeds all unboosted variants of these Pokemon. The only other move to really even consider on this set is Hidden Power Ice, as it is the only move Rotom-C has that actually does any sort of decent damage to Druddigon, scoring a 2HKO with the boost from Choice Specs.

This Rotom-C really appreciates entry hazard support to maximize its wallbreaking potential. With Stealth Rock alone, Rotom-C is able to seriously dent or outright KO most Fire-types with Thunderbolt. Pokemon such as Smeargle, Druddigon, and Uxie can set up Stealth Rock with relative ease. Spikes support is also welcomed, as most of Rotom-C's checks are grounded. Qwilfish, Accelgor, and Scolipede are all fine options for such support. Steel-types such as Steelix and Klinklang are solid teammates for checking Druddigon. The former can set up Stealth Rock while the latter can take advantage of fallen Water- and Fire-types and prepare a sweep with Shift Gear. As Choice Specs Rotom-C really doesn't have any "counters" in the strictest sense of the word, good offensive teammates are generally those who can capitalize on the Pokemon Rotom-C defeats. Choice Scarf Emboar is a prime example of this. It can check most Grass-types that switch into Rotom-C's STAB moves and it will have a much easier time cleaning up with Flare Blitz once Rotom-C weakens or KOes the opponent's Water- and Fire-types. Omastar, offensive Accelgor, and Entei are other examples that have an easier time sweeping or cleaning when Water- and Fire-types are removed.

While Rotom-C is one of the best Choice item users in RU, one shouldn't forget its useful resistances to Electric-, Water-, and Grass-type moves. With this set, Rotom-C has more flexibility in its play, as it can check many top threats such as Slowking and Sceptile while still posing as a legitimate offensive threat, as it still has the same power as the Choice Scarf set. Rotom-C's STABs really shine here, as they hit many common physical attackers in RU for super effective damage.

Will-O-Wisp is Rotom-C's status move of choice on this set. The resulting burn cripples many physical attackers; Druddigon, Gallade, and Escavalier are just a few of the Pokemon shut down by a burn. However, be aware that most offensive variants of Gallade do run a Lum Berry. If slowing down the opposing team is more beneficial to its team, Rotom-C can opt to use Thunder Wave as its status move. This allows it to cripple physical and special attackers alike. Volt Switch is preferred in the next slot as it retains Rotom-C's overall utility and scouting abilities. If power is desired over general utility, Thunderbolt can be used over Volt Switch to give Rotom-C a way to go on the offensive without being forced to lower its Special Attack. Leaf Storm is an absolute must in the third slot, as it lets Rotom-C directly deal with the likes of Golurk and Rhydon without having to resort to burning them. Thanks to its ability to switch moves, Rotom-C can use Leaf Storm much more freely than either of the Choice sets, as it can Volt Switch out after using Leaf Storm. In the final slot, Rotom-C can use either Pain Split or Hidden Power Fire. Although it's fairly unreliable, Pain Split is Rotom-C's only means of recovery outside of Rest. Hidden Power Fire provides Rotom-C with a means of damaging Grass-types such as Sceptile, Ferroseed, and opposing Rotom-C.

The EV spread allows Rotom-C to outspeed all positive base 80s. However, if the extra Speed isn't needed, Rotom-C can choose to invest more in its bulk. An alternate spread of 168 HP / 252 SpA / 88 Spe with a Modest nature can be used to gain more bulk to take hits with while still outspeeding the likes of Omastar and Bouffalant. However, the inability to outspeed Gallade and Kabutops hurts Rotom-C's ability to keep them in check.

This Rotom-C really appreciates teammates that can handle Fire-types, as all of them can come in for free on Will-O-Wisp and resist Leaf Storm. Qwilfish, Rhydon, and Slowking can check Fire-types and support Rotom-C in various ways. Most Grass-types can switch into Rotom-C with relative ease, although Thunder Wave and Hidden Power Fire can catch them by surprise. Still, a check to them will ease the pressure on Rotom-C. Fire-types such as Emboar, Moltres, and Entei can handle most Grass-types. Alternatively, you can turn to Sap Sipper Pokemon such as Bouffalant and Miltank to handle opposing Grass-types. Wish support can help Rotom-C stay around longer as Pain Split is far from reliable. Alomomola is perfect for this, as it's one of the best checks to Entei and Emboar in RU and it also possesses the largest Wish in the tier. Although this set is more supportive, entry hazard support is still appreciated. Rhydon, Druddigon, and Qwilfish are all capable of providing such support and checking various Fire-types for Rotom-C. Druddigon can even check various Grass-types.