The player first meets Tangrowth as the unusual resident of Pokémon Pokopia’s abandoned town.
The game begins after Ditto awakens and transforms into a human. In the withered settlement, a peculiar-looking Tangrowth has been living alone. This Tangrowth becomes Ditto's first major companion and helps establish the game's rebuilding premise.
Tangrowth is presented as a special character called Professor Tangrowth by other Pokémon. It has a partially white body and wears what appear to be human tools, giving it a distinctive appearance compared with an ordinary Tangrowth.
Professor Tangrowth teaches Ditto the basics of town life. Together, the pair begin restoring habitats and making the deserted environment more comfortable for Pokémon that gradually return to the area.