Turtwig is a Grass-type Tiny Leaf Pokémon in Turtwig in Diamond and Pearl, Trainers must first acquire the National Dex.
The National Dex is an the base Sinnoh Dex players have throughout Pokémon BDSP's main story. This PokéDex upgrade is provided to Trainers after beating the Elite Four, becoming the League Champion, and seeing all 150 Pokémon in the Sinnoh region. Once these accomplishments have been achieved, fans can speak to Professor Rowan and Professor Oak to receive the National Dex. With this PokéDex feature now obtained, players must head into the Grand Underground of Diamond and Pearl.
Turtwig can be encountered within several zones of the Grand Underground — Sunlit Cavern, Still-Water Cavern, Riverbank Cave, or Grassland Cave. Trainers can visit each of these locations separately, or they can refresh a particular area's wild Pokémon spawn by exiting and re-entering. Turtwig can appear at Levels 16 - 63 in the Grand Underground of Pokémon BDSP.
Evolving Turtwig in Pokémon BDSP
Turtwig's evolutionary process is very straightforward, requiring players to level the Pokémon to specific milestones. First, Turtwig will become Grotle once it attains Level 18. Trainers who captured Turtwig at a level higher than 18 can evolve it by having it reach the next level. The easiest way to do this is by feeding it a Rare Candy, a consumable that instantly grants a level up to any Pokémon. Grotle is a Grass-type Grove Pokémon equipped with Overgrow and Shell Armor. Overgrow boosts the power of Grotle's Grass-type moves by 1.5× when its HP falls below a third of its max, and Shell Armor is a defensive Hidden Ability that prevents Grotle from receiving critical hits.
To evolve Grotle into Torterra, Trainers must level the Grove Pokémon to 32. If players find the leveling process tedious, they can give Grotle a Lucky Egg. Lucky Eggs in Pokémon BDSP are items that can increase the EXP gained from battles by 50%. With such a boost, Grotle can reach Level 32 more quickly to evolve into Torterra. Torterra is a Grass- and Ground-type Continent Pokémon equipped with the same moveset as Grotle. In addition, however, all the base stats are increased, with Torterra's Attack being notably higher than Grotle's.
Pokémon Brilliant Diamond and Shining Pearl are available on Nintendo Switch.