Unlike most Pokémon games, evolution in Pokémon Legends: Arceus isn’t automatic. You need to meet certain requirements and evolve them manually in your satchel. Stantler is much the same.
To evolve Stantler into Wyrdeer, a Normal/Psychic Pokémon unique to Hisui, you need to use Psyshield Bash 20 times in Agile Style. Stantler automatically learns Psyshield Bash at level 21. You can unlock the move’s Strong Style if you use Psyshield Bash in battle and level up until it’s mastered.
After, you’ll get an Evolve prompt on your screen. Select Stantler in your satchel and enjoy your Wyrdeer.
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Wyrdeer’s unique typing makes it vulnerable to only two types: Bug and Dark. Dark types are uncommon in the game, and its weakness to Bug can be resolved by having a Fire-type Pokémon like Arcanine or Typholsion in your team. Wyrdeer also has equally high HP, Atk, and Sp Atk levels. It’s recommended to boost the effort levels of those three stats to maximize its potential.
There’s just one catch: Stantler becomes much slower when it evolves. If you need to hit hard and quickly, Wyrdeer is not the best Pokémon to use during an encounter.
For more help with Pokémon Legends: Arceus, we at Pro Game Guides have you covered.