In addition to the couple of new Legendary/Mythical Pokemon within the Isle of Armor portion of the Pokemon Sword and Shield Expansion Pass, there are also a number of older Pokemon previously not found within The Galar Region being able to be found as well. These Legacy Pokemon can only be found of the Isle or Armor, and not in the second portion of DLC in the Crown Tundra. When Pokemon Sword and Shield were first released, not all the 809 previously known Pokemon could be found in the Galar Region (which upset many fans). Though all Legacy Pokemon still won't be found after both portions of the Expansion Pass are released, it still will get the National Pokedex Available Pokemon Number closer to what it should be.
Sandshrew, Sandslash
Igglybuff, Jigglypuff, Wigglytuff
Psyduck, Golduck
Poliwag, Poliwhirl, Poliwrath, Politoed
Abra, Kadabra, Alakazam
Tentacool, Tentacruel
Slowpoke, Slowbro
Magnemite, Magneton, Magnezone
Exeggcute, Exeggutor
Cubone, Marowak
Lickitung, Lickiliky
Happiny, Chansey, Blissey
Tangela, Tangrowth
Kangaskhan
Horsea, Seadra, Kingdra
Staryu, Starmie
Scyther, Scizor
Pinsir
Tauros
Porygon, Porygon2, Porygon-Z
Azurill, Marill, Azumarill
Dunsparce
Heracross
Skarmory
Miltank
Whismur, Loudred, Exploud
Carvanha, Sharpedo
Shinx, Luxio, Luxray
Buneary, Lopunny
Lillipup, Herdier, Stoutland
Venipede, Whirlipede, Scolipede
Petilil, Lilligant
Sandile, Krokorok, Krookodile
Zorua, Zoroark
Emolga
Foongus, Amoongus
Mienfoo, Mienshao
Druddigon
Bouffalant
Larvesta, Volcarona
Fletchling, Fetchinder, Talonflame
Skrelp, Dragalge
Clauncher, Clawitzer
Dedenne
Klefki
Rockruff, Lycanroc
Fomantis, Lurantis
Comfey
Sandygast, Palossand
Magearna
Now that you know about the Legacy Pokemon making their return in the Isle of Armor, Click Here to learn about which new Version Exclusives exist!
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