Some creatures in Pokémon Legends Arceus are more difficult to obtain than others. This is particularly the case for all new Hisui developments such as Overqwil. You will absolutely have to have it for the completion of your Pokédex but also the success of the quest The Legend of the Seas! So, to get it, you will first have to capture a Qwilfish from Hisui in order to evolve it later.
Evolve his Qwilfish from Hisui to Overqwil
Once your Hisui Qwilfish has been captured (In the water. Rosa Rugosa Island in the Obsidian Plains + Serenity Bay, Poissigrand Arch and Long-of-the-Islands Beach in the Lazuli Coast), you must put it in your team and teach it the MultiToxic attack. Normally, this is an attack he already knows so if you don't have it, don't hesitate to consult his abilities directly in the menu in order to change him.
Once done, you will need to use Barb Barrage an exact number of 20 times on opposing Pokémon in Power Style only . Be careful, using the Powerful Style costs you 2PP instead of just one.
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