Amanda, as a Snivy, was originally owned by Cedric Juniper, along with a Tepig and Oshawott. Along with a set of similar Pokémon owned by his daughter, Cedric intended to give Snivy to Trainers starting their journeys. However, N broke into the lab in an attempt to liberate the three Pokémon due to his hatred of Pokémon distribution. His attempt was only partially successful, however, as while the Tepig ran away, Snivy decided to go with N, and Oshawott stayed with Cedric.
Snivy debuted in The Case of the Missing Pokémon. At Castelia City, she was spotted by Cheren's Snivy, who attempts to get her attention by waving, only for Snivy to ignore his greeting. She is interrupted by N's Zorua, who tells her to get moving as they make their way to Route 4.
Prior to Special Delivery, Snivy evolved into a Servine and assisted N in knocking White into the Nimbasa Rondez-View Ferris Wheel. N has Servine tease White's Gigi by having her tie Gigi up and hold her into the air. Having no choice, Gigi attacks Servine with an Ember, knocking her away and freeing the Fire Pig Pokémon from her grasp. Having seen enough, White attempts to jump out of the Ferris Wheel and gestures Gigi to do the same. Surprisingly, Gigi goes to N's side, shocking White, who falls out of the car and onto the ground below. As N and Gigi watch White from the Ferris Wheel N sends Servine to White's aid. After White was rescued by Marshal, Servine follows Black while he takes her to the hospital. When White wakes up in the hospital, the first thing she sees is Servine looking from behind the curtain and immediately crawls back under her covers and screams. After White explains her situation, Black angrily tries to get Servine to tell him where N is only for her to arrogantly ignore him.
In Growing Pains, White tried to capture a Deerling to use in the Battle Subway, but she angers the Pokémon and begins to attack White. Much to White's shock, Servine comes to her aid and blocks the Deerling's attack. Even more surprising to White is that when Black suggests that she commands Servine to attack the Deerling, she listens to her commands and helps her catch her.
In With a Little Help from My Friends, Servine battled Ingo's Klinklang. Although White used a strategy to clog Klinklang's gears up with leaves, the battle ends in a tie. When White attempts to give Servine the nickname Amanda, she gets a slap from her tail in response. During a battle with a group of wild Vullaby, Amanda teams up with Bianca's Oshawott and a Meloetta to help defeat the group's leader.
Sometime before White had finished her training on the Battle Subway, Amanda had evolved into her final form, a Serperior. She battled N near Icirrus City along with Black's Bo and Cedric's Samurott. Together the three managed to defeat N's Zorua and Gigi.
In Pink Slip, Amanda was alongside White as she finds the Light Stone. When White is approached by N, she sends out her team to defend herself, but Amanda and Gigi don't attack, as they immediately realized that N wasn't there to fight.
In The Final Battle: Crushed Ambition, Amanda was used to try to keep Kyurem from destroying the Plasma Frigate. Later, Amanda, alongside the other eight Unova starters, fired their Pledge moves at N's Castle to stop the fire caused by the Plasma Frigate.