Sega announced that Sonic 1, Sonic 2, Sonic 3 and Knuckles, and Sonic CD will be delisted from digital storefronts in May in the lead up to the remastered Sonic Origins collection.
Review: Sonic Origins is a tragic example of good classics ruined by greed
Sega are delisting older versions of the classic games in Sonic Origins
Sega is delisting classic Sonic games in May
Sega delisting classic Sonic games in May ahead of Sonic Origins, sonic game
Sonic the Hedgehog – Delisted Games, longplay of sonic origins
Sonic the Hedgehog - Wikipedia
Sega delisting classic Sonic games in May ahead of Sonic Origins, sonic game
Sega delists classic Sonic games ahead of Sonic Origins launch
Sonic Origins Gets Release Date as Sega Delists Classic Sonic Games
Sonic Origins, Sonic Wiki Zone
SEGA is delisting classic Sonic games ahead of Sonic Origins remaster