Crisis at Ferroseed Research! (Japanese: テッシード研究所！アイリスとバイバニラ！！Tesseed Research Institute! Iris and Baivanilla!!) is the 81st episode of the Best Wishes series, and the 738th episode of the Pokémon anime. It first aired in Japan on May 31, 2012 and in the United States on September 29, 2012.
As Ash and his friends head towards a harbor to take the boat to Virbank City, they happen to meet the Dragon Buster Georgia and the "Blizzard Pokémon" Vanilluxe. Much to Iris's discomfort, Vanilluxe takes a closer interest in Axew, which scares both of them before Georgia retrieves Vanilluxe. Georgia dryly remarks that oddly enough, Vanilluxe is primarily interested in making friends with Dragon-types, and informs the group that she's currently on her way to the Ferroseed Research Institute in order to acquire moss that enhances Pokémon's abilities. Ash and his friends find this interesting, and head to the laboratory together with Georgia (to the latter's frustration, who hadn't agreed to the idea of them coming). They are met by Case, one of the assistants to Professor Malveaux, who runs the institute but is away on an academic meeting. Case shows the group around the institute, where Ferroseed latch onto various rocks collected from all over Unova to absorb their nutrients, before ejecting their moss spore-filled spikes which cause moss to grow. One room, in particular, holds three Ferroseed latched onto sparkling stones that Iris identifies as coming from Chargestone Cave; Case confirms that they have only recently begun researching the effects of Chargestone Cave moss. Further along the facility, Case shows various experiment stations where other scientists experiment on the moss's heat resistance, growth rate and durability amongst other properties, in order to uncover practical applications for the moss. As the tour continues, the Chargestone Ferroseed begin to spawn moss all over the floor.
On the top floor, Case explains that their final floor is where research into enhancing Pokémon abilities is done using the moss. Georgia excitedly sends Vanilluxe out, hoping that Case has moss for Ice-types to use, but Vanilluxe chases after Axew who runs away in fright. At the same time, Ash's Oshawott emerges, having become smitten with Vanilluxe and runs after them, leaving Iris to chase after Axew. Case informs Georgia that unfortunately, the institute hasn't found any moss that improves Ice-types, leaving her severely disappointed as she wanted to use moss to change Vanilluxe's personality and improve her abilities. Cilan suggests that moss wouldn't possibly change a Pokémon's personality, and Case promises Georgia to let her know as soon as the research teams find something.
Back at the third floor, the Chargestone moss has begun to escape the room, catching the attention of the other scientists who can only flee from the overgrowth. An emergency is called as the moss begins to make its way to the fourth floor where Ash, Cilan, Georgia and Case are. Ash attempts to have Pikachu stop the moss, but Pikachu catches a whiff of the moss and is instantly incapacitated, forcing the group to retreat to the emergency underground bunker.
By this point, the moss has grown out of the institute and begun to envelop the entire city. Professor Malveaux, who has just returned, quickly enters the bunker where the scientists are monitoring the situation. He diagnoses that Pikachu has become sick from inhaling the Chargestone moss spores, which fortunately have no adverse effects on humans, and prescribes a mix of Lum Berry, Mago Berry and White Herb extract as a cure. A call from Nurse Joy comes in, reporting that Electric and Ground Pokémon all over town have fallen ill; Malveaux confirms that the moss likely has an effect on those specific types of Pokémon. Georgia is relieved that at least, Vanilluxe will not be affected. One of the scientists contacts Officer Jenny for help, and Malveaux adds that the major routes should be sealed off to minimize damage.
On the institute's roof, Iris has caught up with the other Pokémon. Axew jumps into Iris's arms as Vanilluxe teases them both with its cold breeze. The group prepares to leave but are stopped by the mass of moss. Through the intercom, Cilan explains the situation to Iris as Georgia warns Iris about exposing Vanilluxe to harm, but the moss begins growing through the doors and onto the roof. Iris and the others try to flee, but are stopped at the edge of the roof where Iris sees that the moss has completely taken over the city. Oshawott attempts using Water Gun, but the moss is barely affected. Iris sends out her Excadrill and Emolga, but before they can do anything they succumb to the effects of the moss, forcing Iris to recall them. As the moss encroaches near Iris screams for Vanilluxe to do something, and the Snowstorm Pokémon blasts the moss with its Icy Wind. This causes the moss to shatter completely, allowing Iris to proceed. Meanwhile, the group in the basement witness this and realize that Ice-type attacks can neutralize the moss. Malveaux has a message sent out to Officer Jenny, while Georgia volunteers her Beartic to help out.
Outside, Officer Jenny uses a flock of Swanna to clear the moss with Ice-type moves, while Vanilluxe and Beartic separately clear the moss in the institute, allowing everyone to move to the third floor where the Chargestone Ferroseed are. Unfortunately, having absorbed too much energy from the Chargestone rocks, the Ferroseed are unable to control their moss spikes and spray spikes everywhere. Malveaux attempts to use a device to secure the Ferroseed and help drain their excess energy, but the machine breaks down as a result of the supercharged Ferroseed, leaving them to spray more moss spikes. Vanilluxe and Beartic quickly become exhausted from all the moss clearing. At this point, Ash appears with a recovered Pikachu, who had been fed the medicine Malveaux prescribed, and sends out Pignite to down the Ferroseed with Flamethrower. This allows Pikachu to move close enough to drain the excess electricity from Ferroseed, aided by Cilan's Stunfisk. Once the draining is complete, Malveaux runs over to the Ferroseed and apologises to them. Pikachu and Stunfisk are instructed to discharge their electricity through a broken window; nearby, Oshawott is nearly caught by a stray bolt and uses his scalchop to deflect it, inadvertently shocking the rest of the group. Oshawott is surprised by this and moves his scalchop, ending up getting shocked himself. The group collapses after the massive electric discharge.
Outside, Georgia grudgingly compliments Iris on being able to synchronize with Vanilluxe, wondering if she shouldn't become an Ice Master instead of a Dragon Master. Iris is mildly surprised by Georgia's goodwill before declining, and Georgia smirks that it's fine - defeating Iris wouldn't mean anything if she wasn't a Dragon Master, anyway. Georgia departs, leaving the group to head to Virbank City.