A total of 21 Pokémon from the development of Gold and Silver have been included in this game. These include new Pokémon, two baby forms and one evolution for generation I Pokémon, and several beta designs for official Pokémon, which have been implemented as regional forms.

I've taken some liberties with the types, stats, movesets, and evolution methods of these Pokémon compared to what was leaked from the development of Gold and Silver, but in most cases I've tried to maintain much of the original design while making them fit with the rest of the modern Pokédex.

For players who want to catch them all, a list can be found below of all of the beta Pokémon currently available in the game and how to obtain them.

List of Beta Pokémon

Sprite	Name	Type	How to Obtain
	Teddiursa Beta Form	Fire	Long grass on Route 38, morning and daytime
	Ursaflame	Fire	Evolve Beta Form Teddiursa with a Fire Stone
	Tangel	Grass	Long grass on Routes 32 and 33
	Marill Beta Form	Electric/Fairy	Evolve Azurill with high happiness in KantoTrade in Olivine CitySurfing on Route 9
	Marumarill	Electric/Fairy	Evolve Beta Form Marill at level 18Surfing on Route 9
	Molancora	Water	Surfing in Olivine City, Cianwood City, and Routes 12, 13, 34, 40, and 41Fishing with an Old or Good Rod in New Bark Town, Pallet Town,Vermilion City, Cinnabar Island, and Routes 20, 21, 26, 27, and 41
	Angore	Water/Steel	Evolve Molancora at level 38Fishing with a Super Rod in New Bark Town, Pallet Town,Vermilion City, Cinnabar Island, and Routes 20, 21, 26, 27, and 41
	Meowsy	Normal	Long grass on Routes 30, 31, and 33, morning and daytime
	Moibelle	Dark/Fairy	Long grass on Routes 30, 31, 33, and 46, night
	Chimeow	Dark/Fairy	Evolve Moibelle at level 28Long grass on Route 11, night
	Tyker	Electric	Long grass on Routes 43 and 44, morning and daytime
	Straigar	Electric	Evolve Tyker at level 35Long grass on Route 10, morning and daytime
	Swandame	Normal/Flying	Evolve Farfetch'd Kanto Form by leveling up while knowing Slash
	Kurstraw	Ghost/Dark	Burned Tower
	Phandarin	Ghost/Dark	Evolve Kurstraw by leveling up at night while holding a Spell Tag
	Wolfrost	Ice	Ice Path and long grass on Route 46, night
	Warwolf	Ice	Evolve Wolfrost at level 35, nightSeafoam Islands, Mt. Silver cave, and long grass outside Mt. Silverand on Route 28, night
	Hoppip Beta Form	Grass/Psychic	Long grass on Route 34
	Skiploom Beta Form	Grass/Psychic	Evolve Beta Form Hoppip at level 18
	Jumpluff Beta Form	Grass/Psychic	Evolve Beta Form Skiploom with high happiness
	Octillery Beta Form	Poison/Steel	Evolve Remoraid at level 25 in Johto