Which Pokémon was the player’s first major companion in Pokémon Pokopia’s story?

Professor Tangrowth is the player’s first major companion in Pokémon Pokopia’s story.

After Ditto reaches the abandoned world, it meets a Tangrowth known as Professor Tangrowth. This character has been studying the damaged environment and is connected to the mystery of why humans and Pokémon disappeared from the area.

Professor Tangrowth helps establish the game’s central mission: restoring habitats so Pokémon can return and live safely. The character’s scientific role also provides context for the environmental problems surrounding the island and the clues left behind by humanity.

Other named Pokémon join the story later. Chef Dente is a Greedent, DJ Rotom is a Rotom possessing a stereo, Smearguru is an artistic Smeargle, and Mosslax is a Snorlax covered with plant growth. Those characters are memorable, but Professor Tangrowth is the early guide linked to Pokopia’s central mystery.