Rocking the Virbank Gym! Part 1 (Japanese: 激闘タチワキジム！VSホミカ(前編）Fierce Fighting at Tachiwaki Gym! VS Homika!! (Part 1)) is the 83rd episode of the Best Wishes series, and the 740th episode of the Pokémon anime. It first aired in Japan on June 14, 2012 and aired in the United States on October 13, 2012.
On their way to the Virbank City Gym, our heroes are surprised to come across several Trainers who are still reeling from their defeat at the hands of the Gym Leader, Roxie, who specializes in Poison-type Pokémon. With Cilan’s help, Ash discovers the Gym in an underground music club, where Roxie is the leader of the punk-rock trio known as Koffing and the Toxics. Roxie accepts Ash’s challenge, on one condition: she wants him to use all six of his Pokémon against her team of three! Ash is a little unsure about this, but she assures him that he’ll appreciate the numbers advantage. He agrees, and the unusual battle begins—in front of a crowd of rowdy fans and with plenty of musical accompaniment!
First up, it’s Roxie’s Koffing versus Ash’s Boldore. But, as the losing Trainers warned, Roxie proves to be extremely powerful and resourceful, and Boldore is quickly eliminated. Ash sends out his Unfezant next, hoping a Flying type will be able to keep up with Koffing’s incredible speed—but it’s just not enough, and Unfezant is knocked out.
Ash’s third Pokémon is Leavanny, much to everyone’s surprise—as a Grass-type Pokémon, it’s at a disadvantage against Poison-type foes. But Ash has a strategy this time, and he directs Leavanny to wrap Koffing up with a String Shot and reel it in for a close-range Energy Ball. Koffing is finally eliminated, and Roxie is one Pokémon down!
Next, she sends out her Scolipede, and it uses Toxic to send Leavanny reeling! Will Ash be able to recover from this poisonous assault and win his eighth Gym badge?
Meanwhile, Team Rocket talks to Dr. Zager through a video feed from within their truck hideout. They report that they have lost track of Meloetta since it can disappear. Dr. Zager plans to send them anti-cloaking glasses, which the trio malevolently accept.
The next morning, Ash is running through the streets in search of the Gym. Cilan points out that the Gym is actually beyond an unassuming metal door. The group heads down a flight of stairs and enters the stadium just as a Trainer and his Gothitelle are defeated. The Gym Leader is Roxie, the bassist and frontwoman of Unova's top punk band "Koffing and the Toxics". The band was named after Roxie's main Pokémon, Koffing, which she met at a concert in Kanto. The Gym not only serves as a battlefield, but also a live concert stadium. The screams of an audience that loves both battles and live concerts fill the air, and Ash livens up the stadium with a Thunderbolt from Pikachu. Brimming with confidence, Roxie makes the outrageous suggestion that Ash will battle with six Pokémon while she will only use three. Ash attempts to persuade her otherwise given that this type of battle is unfair, but she insists to do it anyway. From behind a stage light, Meloetta observes the upcoming battle.
Roxie chooses Koffing as her first Pokémon, which surprises Cilan and Iris with its incredible Speed. Ash brings out Boldore as his first Pokémon. The band rocks out before the battle begins, and the crowd chants Ash's name, confusing him and his friends. With that, the referee begins the battle. Ash has Boldore use Sandstorm to slow down and cause steady damage to Koffing. Roxie isn't bothered and has Koffing counter with Clear Smog, which blows away the Sandstorm and deals considerable damage to Boldore. However, it stands its ground and uses Rock Blast, but Koffing deflects with Gyro Ball and strikes Boldore for super-effective damage. Koffing then uses Sludge Bomb and Boldore counters with Flash Cannon. Koffing then uses Gyro Ball, which Boldore attempts to defend against with Sandstorm, but Koffing breaks through and knocks Boldore out.
Ash sends out Unfezant next to counter Koffing's speed, starting off with Quick Attack which does considerable damage. Koffing then proceeds to use Will-O-Wisp, but a cleverly executed Gust from Unfezant blows the wisps back at Koffing for a lot of damage. Iris and Cilan compliment Ash on his move and Meloetta is shown smiling. Unfezant uses Air Cutter, but Koffing easily dodges and follows up with Sludge Bomb. The smoke clears and it appears that Unfezant has been poisoned as per Roxie's battle style. Koffing then uses Clear Smog to ramp up Unfezant's damage. Ash considers withdrawing her, but she lands and stands her ground confidently. Ash is pleased and calls for Aerial Ace. She clashes with Koffing's Gyro Ball and is knocked back. Unfezant tries once more, but this clash renders her unable to battle. With that knockout, Ash is left with four Pokémon.
Ash surprises everyone when he brings out his third Pokémon, Leavanny, a part Grass-type. Ash feels confident about his choice and has Leavanny use Energy Ball. The attack hits and has a secondary effect on Koffing: lowering its Special Defense. Roxie goes for a head-on attack with Gyro Ball, but Leavanny ensnares it in his String Shot. Koffing then tries to use Sludge Bomb but misses when Leavanny begins swinging it around. Ash has Leavanny reel it in and finish it off with a close-range Energy Ball that knocks Koffing out at last.
Roxie brings out her next Pokémon, Scolipede. Leavanny fires Razor Leaf, but the move hits with no observable effect. Scolipede responds with Toxic, making Leavanny badly poisoned. Unable to stand due to the poison's effects, Leavanny falls to the ground as the episode ends.
Prior to the start of the episode in the original Japanese airing, a clip of Ash, Pikachu, and the text "Pokémon Movie & TV Anime 15th Anniversary" (Japanese: ポケモン映画＆ＴＶアニメ １５周年), with multiple anime characters saying "Pokémon Anniversary", is presented. This was also shown the airing before the episodes after BW084.