Basculegion is a special evolution of White-Striped Basculin (and only that version) from the Hisui region and it’s now made its way to the future to be a part of the Pokémon Scarlet and Violet: The Teal Mask DLC.
You will need to specifically find a White-Striped Basculin and evolve it by having it deal recoil damage to itself (sad!), a process we’ve detailed below.
Where to find White-Striped Basculin in Pokémon Scarlet and Violet
You can find White-Striped Basculin in The Timeless Woods in Kitakami. The Basculin we caught in Timeless Woods was level 73, making its evolution process pretty easy — though your Basculin may be at a lower level depending on how far you are in the base game before coming to Kitakami.
How to evolve Basculin into Basculegion
The evolution method is unchanged from Pokémon Legends: Arceus: Your Basculin has to take 294 damage or more in recoil damage without fainting (but you can heal between fights). After doing this, just level them up (through natural means or with candy) to evolve them.
Basculin learns three different moves that cause recoil: Take Down at level 36, Wave Crash at level 44, and Double-Edge at level 52.
To complete this, we recommend taking your Basculin to an area with Pokémon roughly 20 to 30 levels below it. (For our level 73 Basculin, we took it to Casseroya Lake in Paldea.) Spam any of the three moves against everything in sight, but make sure to heal so your Basculin doesn’t faint.
Keep tabs on how much damage your Basculin took from recoil by using a notepad (digital or real) so you don’t lose track.
Basculegion will look angry with red details if it’s male and yellow with light blue details if it’s female.
Looking for new Pokémon from The Teal Mask? Learn how to evolve Poltchageist into Sinistcha.