The Sun Moth has descended from the heavens to wreak havoc upon the land below. Volcarona was a monster when first introduced with many grateful for Stealth Rock's existance for keeping it in check. Now, with Heavy Duty Boots, Volcarona is prepared to tear through everything with a vengeance.
The Blazing Dawn
Volcarona
Ability: Flame Body
Item: Heavy Duty Boots
-Quiver Dance
-Fiery Dance/Fire Blast
-Bug Buzz
-Psychic/Giga Drain/Hurricane
Nature: Timid (+SPE, -ATK)
EVs: 4 HP/252 SATK/252 SPE
Volcarona is terrifying after a single Quiver Dance. Volcarona using Quiver Dance is about the same as a Salamence using Dragon Dance (they have the same base speed and offensive stat, and the SDEF boost from Quiver Dance roughly matches the ATK drop from Intimidate). Some calcs:
+1 252 SpA Volcarona Fire Blast vs. 252 HP / 252+ SpD Clefable: 213-252 (54 - 63.9%) -- guaranteed 2HKO after Leftovers recovery
+1 252 SpA Volcarona Fire Blast vs. 248 HP / 252+ SpD Assault Vest Amoonguss: 306-362 (70.9 - 83.9%) -- guaranteed 2HKO
+1 252 SpA Volcarona Fiery Dance vs. 252 HP / 4 SpD Corviknight: 458-542 (114.5 - 135.5%) -- guaranteed OHKO
+1 252 SpA Volcarona Psychic vs. 252 HP / 0 SpD Kommo-o: 290-342 (81.9 - 96.6%) -- 18.8% chance to OHKO after Stealth Rock
+1 252 SpA Volcarona Psychic vs. 252 HP / 252+ SpD Toxapex: 170-202 (55.9 - 66.4%) -- guaranteed 2HKO after Black Sludge recovery
+1 252 SpA Volcarona Giga Drain vs. 4 HP / 0 SpD Azumarill: 304-358 (88.8 - 104.6%) -- 31.3% chance to OHKO
+1 252 SpA Volcarona Bug Buzz vs. 0 HP / 4 SpD Kingdra: 237-279 (81.4 - 95.8%) -- 56.3% chance to OHKO after Stealth Rock
+1 252 SpA Volcarona Psychic vs. 0 HP / 4 SpD Dragapult: 191-225 (60.2 - 70.9%) -- guaranteed 2HKO
After a single Quiver Dance, Volcarona blasts through many of OU's bulkiest threats. Furthermore, can easily come in safely on many defensive pivots and checks, especially Steel types who want nothing to do with Volcarona and are often the back bone to a team's defense, giving Volcarona many opportunities to setup. And with Heavy Duty Boots, it can do this several times throughout a game without having to worry about Stealth Rock and other entry hazards ruining its shenanigans. Fire STAB is up to preference. Fiery Dance is good damage and more setup all rolled into one move, allowing Volcarona to apply even more pressure while it is sweeping, while Fire Blast is great for blasting through the toughest of opponents. Bug Buzz is reliable secondary STAB, wrecking Slowbro and Hydreigon. Final move is up for preference. Psychic tends to be the move of Choice, as it hits most Pokémon that resist Volcaron'a STABs (Kommo-o, Dragapult, and Toxapex) hard. Giga Drain's main considerations are that it hits Azumarill harder and provides Volcarona with some healing for longevity. Hurricane is a niche choice, hitting only Kommo-o hard, but is a nasty surprise for opposing Rain teams (or consideration to throw Volcarona on your own).
As for speed calcs, Base 100 has always been a popular speed tier with many, many dangerous threats a base speed 100. After 1 Quiver Dance, a Timid Volcarona will outspeed the entire unboosted tier (492 vs Zeraora's 423). Timid is strongly recommended for the game of inches with other similarly fast threats (i.e. Timid Scarf Hydreigon will outspeed a Modest Quiver Danced Volcarona)
Other Options
Defog -with Heavy Duty Boots Volcarona makes a decent Defogger
Tailwind/Rage Powder -great doubles options
Checks and Counters
Chansey -Chansey is just far too bulky for Volcarona to break through, requiring 3 Quiver Dances for a Modest one to threaten a 2HKO (though a Timid one can do similarly if Sunny Day is in effect). Chansey can always come in safely, heal up with Softboiled and beat Volcarona down with Seismic Tosses.
Dragapult -(Physical only) Dragapult can always live at least one hit even after a Quiver Dance and a +Life Orb Dragon Darts is a guaranteed OHKO on sweeper Volcarona
Physical attackers -Volcarona's physical bulk is abysmal and can't take physical hits for beans. Predicting a Volcarona switch in and switching to a physical attacker can prevent Volcarona from setting up, just be aware that an unlucky Flame Body activation can mean your attacker is crippled for the rest of the match.
Knock Off+Stealth Rock -remove Volcarona's item and Stealth Rocks will maim Volcarona, severely limiting its options. Knock Off works great for this as the damage Volcarona takes from the attack will likely push it into Stealth Rock kill range.
