Moves
Fire Blast does tremendous damage against nearly all foes that are weak or neutral to it. It OHKOes Virizion, Mega Glalie, Escavalier, Rotom-C, and Sigilyph, it has a chance to OHKO Scrafty after Stealth Rock damage, and it 2HKOes Aromatisse and most Meloetta sets. Earth Power hits the Fire- and Rock-types that resist Fire Blast super effectively, as well as Electric- and Poison-types. It OHKOes Emboar, Delphox, Houndoom, Choice Band and Rock Polish Rhyperior, Qwilfish, Swords Dance Drapion, and Jolteon, and it 2HKOes Alomomola, Seismitoad, and Jellicent, though Jellicent can use Recover repeatedly to stay ahead of Mega Camerupt's damage output and has a high chance to OHKO Mega Camerupt with Scald after Stealth Rock damage. Stealth Rock provides valuable team support. Toxic cripples many of Mega Camerupt's switch-ins, such as Alomomola, Flygon, and Seismitoad. Hidden Power Ice is a guaranteed OHKO against offensive Flygon and has a good chance to OHKO defensive Flygon after Stealth Rock damage. Flamethrower can be used over Fire Blast for greater accuracy at the cost of power. Will-O-Wisp could also be used to cripple foes, but Toxic is better at wearing down Alomomola and Jellicent.
Set Details
176 EVs in Special Attack and a Modest nature allow Mega Camerupt to do massive damage and secure a 2HKO on Alomomola. 84 EVs in Speed allow Mega Camerupt to outspeed uninvested Cofagrigus. On the turn that Camerupt Mega Evolves, it outspeeds uninvested base 50 Speed Pokemon, such as Rhyperior and Registeel. 248 EVs in HP improve Mega Camerupt's overall bulk. Solid Rock on non-Mega-Evolved Camerupt helps it take less damage on a poorly predicted switch in. A more defensive spread of 248 HP / 176 Def / 84 Spe with a Bold nature can be used to check Emboar. Another alternate spread of 248 HP / 176 SpD / 84 Spe can be used to check Houndoom, Delphox, Jolteon, and Rotom-C, though these spreads come at a major loss in power and reduce Mega Camerupt's ability to break through Alomomola, Jellicent, and Mega Audino.
Usage Tips
Mega Camerupt pressures the opponent into switching, which gives it an opportunity to set up Stealth Rock or hit a foe on the switch. One of the major challenges of Mega Camerupt is knowing when to switch it in. As a result, Mega Camerupt benefits tremendously from good prediction. Predicting Volt Switches from Rotom-C, Magneton, Jolteon, and Eelektross gives you a free switch to Mega Camerupt and nets a free turn if the foe is holding a Choice item. Mega Camerupt is also a good sponge for a predicted Knock Off from Escavalier, Drapion, Sneasel, or Eelektross, as well as a predicted Trick from Rotom-C, Choice Scarf Delphox, or Choice Scarf Meloetta. Thanks to its typing, Mega Camerupt can also switch freely into Will-O-Wisp and Thunder Wave. Toxic should be used when anticipating a Water-type switch-in, such as Alomomola, Seismitoad, or Jellicent, as this will help wear them down throughout the rest of the match. If running Hidden Power Ice, try to hit Flygon on the turn it switches in.
Team Options
Healing Wish support from Mesprit, Audino, or Musharna helps Mega Camerupt survive longer and punch more holes into the opponent's team. Wish support from Alomomola, Aromatisse, or Audino helps Mega Camerupt last longer on more balanced teams. Mega Camerupt appreciates Heal Bell or Aromatherapy support to prevent it from being worn down by poison damage, so Uxie, Aromatisse, Audino, Vileplume, Togetic, Lanturn, Musharna, Granbull, and Lapras make for good partners. Trick Room turns Mega Camerupt's low Speed into an advantage, so setters such as Aromatisse, Cofagrigus, Musharna, Bronzong, Smeargle, and Uxie synergize well with it. Mega Camerupt appreciates switching in safely, so VoltTurn support from Jolteon, Rotom-C, Magneton, Lanturn, Eelektross, Flygon, Meloetta, and Uxie helps. A good way to mitigate Mega Camerupt's poor Speed is by paralyzing foes, so paralysis spreaders make for effective teammates, such as Qwilfish, Druddigon, Granbull, Uxie, and Jolteon.
While Mega Camerupt generally runs Stealth Rock, it appreciates other Stealth Rock setters, such as Uxie, Mesprit, Druddigon, Seismitoad, Bronzong, Omastar, and Smeargle, so that it can run both Toxic and Hidden Power Ice. Spikes support from the likes of Qwilfish, Omastar, Garbodor, Accelgor, and Smeargle can help Mega Camerupt more easily OHKO or 2HKO foes. Qwilfish and Garbodor are also helpful for absorbing Toxic Spikes, which would otherwise wear Mega Camerupt down. Bulky Water-types, particularly those with Water Absorb or Storm Drain, help to patch up Mega Camerupt's weakness to Water-type attacks, so Seismitoad, Lapras, Mantine, Alomomola, Lanturn, Pelipper, and Qwilfish are great options that appreciate Mega Camerupt's ability to check Grass-types. Defog and Rapid Spin support prevents Mega Camerupt from being worn down as easily, so Flygon, Togetic, Shiftry, Hitmonlee, and Kabutops make for good partners.
Electric-types such as Jolteon, Eelektross, Magneton, and Rotom-C pair well with Mega Camerupt for their ability to check Water- and Flying-types. Eelektross and Rotom-C synergize particularly well with Mega Camerupt because of their immunity to Ground-type attacks. Grass-types such as Shiftry, Vileplume, and Virizion also help against Water-types, as well as Ground-types. Mega Camerupt's offensive prowess is appreciated by late-game cleaners such as Sneasel, Hitmonlee, Fletchinder, and Medicham because it allows them to sweep more easily.