Swablu is a Normal and Flying-type Cotton Bird Pokémon in Pokémon Brilliant Diamond and Shining Pearl that evolves into Altaria after reaching a certain level milestone. Although Swablu doesn't provide much utility in battle, its main appeal is its rarity within the player Pokédex. There are two methods of catching a Wild Swablu. The first requires that Trainers have the PokéRadar, a special device that is only obtainable once players have beaten the main story of Pokémon BDSP.
After beating all the Gym Leaders, becoming the League Champion, and obtaining the National Dex from Professor Oak, players will also receive the PokéRadar. Afterward, they can use the PokéRadar on Route 211 for a 5-20% chance of encountering Swablu. However, it is strongly recommended that Trainers use the second method of finding Swablu by exploring the Grand Underground. Yet, Trainers will need a Key Item known as the Explorer Kit to go to the Grand Underground.
Related: Pokémon BDSP: How to Get (& Evolve) Mareep
To get the Explorer Kit in Pokémon BDSP, fans must travel to Eterna City and head into the house that sits to the right of the PokéMart. Inside, players can speak to a bald gentleman named the Underground Man. After some brief dialogue, he will gift Trainers the Explorer Kit, which allows instant access to the Grand Underground in Diamond and Pearl as long as the player is in an outdoor area. Beneath the surface of the overworld, Trainers can now begin their search for Swablu.
Swablu can be found within Whiteout Cave, Spacious Cave, Icy Cave, Glacial Cavern, or Fountainspring Cave. Trainers can head into each zone until a Swablu appears, or they can exit and re-enter a single room until Swablu is among the refreshed spawns of Wild
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