In the eastern part of Nimbasa City lies its amusement park which sports various facilities, including its signature Rondez-View Ferris Wheel. Black stands in front of a flashy building next to a giant Pikachu figure, and tells Musha that the park seems to be full of fun. However, their main aim there today is to challenge the Nimbasa Gym, which interior is also built like an amusement park.

Black steps into the building, and sees that the entire room is essentially a huge rollercoaster system which has maze-like railways connecting a multitude of transparent platforms. The Gymleader, Elesa, who is also a top fashion model and idol, shows up on the railway on a scooter-like cart, and tells Black that there are switches on each platform to change the course of the tracks. Basically, the challenger will have to find his way through the rollercoaster puzzle to reach the end, where she will be waiting.

The young woman wishes Black good luck, and speeds away with a wink. Black climbs into a coaster car with Musha, and as soon as the glass cover is lowered, the car starts dashing along the railway, turning at abrupt angles and even doing vertical loops at some point. Every time the car stops at a platform, Black lifts the glass cover to catch his breath, and finds himself on an unexpected spot. He grunts that it seems harder than it looks to get to where he wants, and decides to ask for Musha's help.

On the Gymleader's platform, Elesa watches as the Munna clamps on Black's head, and the boy immediately goes into a contemplative mode. A minute later, he steps back into the coaster car, and appears to know exactly what he should do now. He accurately sets the switches in place, and arrives on her platform in no time.

Elesa congratulates him for reaching her, but as Black lifts the glass cover once more, he discovers that the overhead safety bar would not unlock. He thrusts it several times, all to avail, and believes that it must be malfunctioning. Elesa checks on the safety bar herself, and fears that it is indeed broken. She offers to let Black come back another day to continue challenge, but the boy frantically refuses, and opts to start the battle like that.

The young woman grins that Black is as impulsive as she has heard, and tells him that he will have no right to complain if he loses since he made the choice. She announces that it will be a 2 vs 2 switch-in battle, and proceeds to send out her Zebstrika, while Black calls out Tula from its Pokeball.

In that instant, Black's coaster car suddenly starts moving, and the boy cries out in horror as he is sent onto the railway once again. Elesa remarks that it is why she suggested a rematch, but on a deeper thought, thinks that it is rather exciting, as she has never done something like that before.

Holding his cool, Black orders an Electro Ball from Tula, and the electric spider hurls a sparkling globe towards Zebstrika while still on the moving car. The attack hits the zebra right in the chest, but to Black's surprise, it quickly recovers and starts chasing after him on the tracks at an unbelievably high speed. In a matter of seconds, it catches up with the coaster car, and delivers Flame Charge, which burns and knocks out Tula instantly. Black is bewildered by Zebstrika's agility, and Elesa explains that when Galvantula hit it with an electric type attack, it activated its Motor Drive ability, raising its speed sharply. She is surprised that Black isn't aware of this, and reminds him that he is challenging the number one electric type expert in Unova.

Black grunts in frustration, since it is indeed something which he should know after such an extensive research on Elesa, but he has never expected to have his challenge in a coaster cart, which definitely affected his judgment. On the other hand, Elesa herself has never battled in such a situation either, which he thinks makes them equals.

Black retrieves Tula into its Pokeball, and sends out Nite. The Pignite quickly engages in a close-up combat with Zebstrika, and despite the speed difference, adeptly evades all of the electric zebra's kicks. Elesa is impressed by Nite's swiftness and footwork, since its bulky body would suggest it being slow, and Black states that its evolution has equipped it with the fighting type, raising its skills in the physical department.

The Nimbasa Gymleader wonders exactly how agile it can be, and orders a Volt Switch from Zebstrika. Nite jumps into the air to avoid the electric currents, and Black orders it to retaliate with a kick. However, just as Nite is about to land its blow, Zebstrika suddenly disappears. The confused Pignite frantically looks around for its opponent, and subsequently gets ambushed from behind from Emolga.

Black bolts in shock, wondering how Emolga entered the battlefield in the first place, and Elesa grins that Volt Switch is one of her signature moves, which incorporates attack and switching in a single motion. Emolga delivers a Volt Switch to smack at Nite's face, but just as Nite thrusts its arm forward to strike, the electric squirrel vanishes, and Zebstrika materializes again, ramming its powerful forelegs into the unsuspecting Pignite.

The same process goes on for a few turns, and Black, who is still circulating on the railway, grunts that he must find a way to counter the rapid succession of assaults. As Emolga fires another Volt Switch to hit Nite from the back, Black grabs the chance and orders a Bulldoze. Nite thumps its heavy body onto the ground to pull of the attack, right at the moment Zebstrika reenters the field, and the supper-effective move instantly knocks out the electric zebra.

Elesa is slightly surprised that the Pignite packs such a move, but thinks the battle is as good as over anyway, since Pignite is already worn out from all the damages it took. She remarks that it will not be able to land its attacks on Emolga as long as it is hovering, and if Bulldoze is the trump card Pignite has for this battle, she can already see Black losing.

With that, Elesa orders Emolga forward, and the electric squirrel skydives towards Nite, striking it with an Aerial Ace. Black is bewildered by its speed, and Elesa believes that the next move will finish his Pignite off. She wants to know why Black did not use his Munna to turn on his detective senses, just like he did while solving the rollercoaster maze, and thinks it might help him figure out a way to handle the situation. However, Black declares that he will not do it, because he is in a Pokemon battle, and he never does that in a Pokemon battle.

The boy states that as the trainer of his Pokemon, he shares a coach and athlete relationship with them, and it will be his failure as a coach if he could not figure out the strategy in a match and turn to his athletes for help instead. That said, he will find a way out of this situation by himself, and not resort to gimmicks from his team members…

Elesa is impressed by his big words, and hopes that he can show her what his strategy is in that case. She motions to Emolga, and the electric squirrel gets ready as Black's coaster car enters another vertical loop, planning to strike with another Aerial Ace when the car comes down from the height. Black looks around as he thinks hard, and knows that a good trainer will utilize everything, including the weather, the landscape, the abilities, and even his current unexpected situation.

The coaster car reaches the highest point of the loop and starts coming down, and Elesa commands Emolga to attack. However, as the electric squirrel skydives towards its opponent, it sees that Nite is not on the car. Confused, it looks around, and it turns out that Nite has stayed at the highest point of the loop by grabbing onto the railway. It times the moment Emolga is hovering right beneath it, and let goes to deliver a downward strike with its forearm, which lands directly on Emolga's face, fainting it in the process.

Elesa realizes that Black has pulled off an aerial battle by using the vertical loop, and grins that Black took good advantage of his situation of being stuck in the coaster car. She states that Black has outsmarted her, and declares him the winner of the battle. She takes out the Bolt Badge, which is a symbol of victory at the Nimbasa Gym, but just as she is about to give it to Black, the coaster car moves and ends Black spiraling on the railways once more.

This time, it enters a track that leads to the outdoors, and Black cries out in horror as he speeds out through a hole in the Gym's side walls. As soon as he gets out, he is hit by a heavy downpour, and he is surprised at the weather condition since it isn't supposed to rain like that during the season. Just then, he spots a silhouette hovering next to the coaster track ahead, which soon reveals itself to be a blue genie-like creature who sits on a cloud with a single horn on its head and a long tail made of grenades.

Without warning, the creature zaps Black with a highly charged electric blast, and Black is instantly charred with his hair smoking and sticking out to the sides. When the coaster car returns indoors and takes him back to the Gymleader's platform, Elesa and Nite gasp at his condition and hurriedly check on him. Black stutters that he is alright, and also points out that the shock has actually helped unlock the overhead safety bar.

Elesa helps him get out of the coaster car, and Black explains what he just saw. The Nimbasa widens her eyes in surprise when she hears that the boy just encountered a one-horned creature who fired electric bolts, and believes that it is the same being she saw as a child when she visited her granny on Route 7 many years ago. Back then, her Zebstrika was still a Blitzle, and her granny told her that what she saw was one of the two flyers of Unova, the bolt strike Pokemon, Thundurus, whose counterpart is the cyclone Pokemon, Tornadus.

Elesa reveals that it was actually Thundurus who inspired her to become an expert in electric types, and says she has looked into the folklore and even searched and tried to capture it. She remarks that Thundurus is said to be able to circle around the entire Unova region in just one day, and Black is really lucky to have seen it today.

Later, as Black leaves the Nimbasa Gym, he is surprised that it has become sunny again, almost as if it never rained. He thinks of Virizion which he appeared momentarily to him at the Pinwheel Forest, and now Thundurus, and realizes that there are a lot of Pokemon which he doesn't know of.

Feeling glad about beating his fourth Gym, the boy pins the Bolt Badge to his jacket's collar, and tells Nite that they should get back and meet up with the president now…