In Lapras of Luxury! Ash received a call from Professor Elm that he had to go to the Marine Pokémon Laboratory to pick up an Egg that he was supposed to bring to Mt. Silver. The next episode it hatched into Larvitar and became very close to Ash and his Pikachu, but Hardened if anybody else approached it.
It started out very shy and timid, but learned to appreciate life through its adventures with Ash, and learned about the world around it. It made new friends, such as an Elekid, a Slowpoke which later became a Slowking named Arthur and an Unown. Larvitar gains a very courageous attitude in You're a Star, Larvitar! where it manages to rescue a whole bunch of Pokémon from Team Rocket practically by itself. In Address Unown!, an Unown teleported Ash, Brock, and Misty to a dimension which physically manifested images and experiences from Larvitar's life such as Egg shells, representing birth, Elekid plugs, from Here's Lookin' at You, Elekid representing the Elekid it befriended, and Slowking crowns, from A Crowning Achievement representing Arthur the Slowking. Ash and his friends then reached a giant Larvitar Egg with holes in it, as well as a large crystalline thorn. Inside the holes were images of Ash, Misty, and Brock, however both Misty and Brock were black and white, symbolizing Larvitar's distrust towards them. When Ash touched the thorn, he was immediately sucked inside along with Misty, Brock, Pikachu and Togepi, putting them in another dimension where Larvitar was seen sleeping. There, Ash, Misty and Brock received visions of Larvitar as an Egg and could hear Larvitar's voice as it was kidnapped by poachers and sensed its mother being brutally attacked. It was later separated from the poachers and mistakenly kicked around. The pain from its past manifested into thorn covered branches encasing Larvitar. Together, Ash, Misty and Brock were able to destroy the branches around Larvitar and help it open up more.
Since that incident, Larvitar opened itself up towards Misty and Brock, but still Hardened around other human beings. It was then reunited with its mother in Mother of All Battles!, who at first believed Ash and his friends to be harming her child. Tyranitar would calm down once she realized Ash and friends' peaceful and benevolent intentions toward Larvitar. However, trouble began when the poachers that initially had stolen Larvitar from her had returned to capture her. Thanks to Ash, Misty, Brock, Ranger Mason and her child (Tyranitar's), the poachers were brought to justice for their crimes. Larvitar was left at Mt. Silver where it could live in peace with its mother and be raised properly under the protection of the mountain rangers.
Personality and characteristics
Larvitar was shy around humans after birth as it would often Harden itself towards them. After awhile, it overcame the shyness and made some Pokémon friends.