Fanatical sale on Sega Mega Drive & Genesis bundle - https://www.fanatical.com/en/bundle/sega-mega-drive-and-genesis-classics-bundle
-75%, £6.25 here.
Contains 59 classic Sega megadrive and genesis games.
"Alex Kidd in the Enchanted Castle, Alien Soldier, Alien Storm, Altered Beast, Beyond Oasis, Bio-Hazard Battle, Bonanza Bros., Columns, Columns III, Comix Zone, Crack Down, Decap Attack, Dr. Robotnik’s Mean Bean Machine, Dynamite Headdy, Ecco the Dolphin, Ecco Jr., Ecco: The Tides of Time, ESWAT: City Under Siege, Eternal Champions, Fatal Labyrinth, Flicky, Gain Ground, Galaxy Force II, Golden Axe III, Golden Axe, Golden Axe II, Gunstar Heroes, Kid Chameleon, Landstalker: The Treasures of King Nole, Light Crusader, Phantasy Star II, Phantasy Star III: Generations of Doom, Phantasy Star IV: The End of the Millennium, Ristar, Shadow Dancer, Shining Force, Shining Force II, Shining in the Darkness, Shinobi III: Return of the Ninja Master, Sonic 3 & Knuckles, Sonic 3D Blast, Sonic CD, Sonic Spinball, Sonic The Hedgehog, Sonic The Hedgehog 2, Space Harrier II, Streets of Rage, Streets of Rage 2, Streets of Rage 3, Super Thunder Blade, Sword of Vermilion, The Revenge of Shinobi, ToeJam & Earl, ToeJam & Earl in Panic on Funkotron, VectorMan 2, VectorMan, Virtua Fighter 2, Wonder Boy III: Monster Lair, Wonder Boy in Monster World"
Yup that's a huge package. Note:
- All games are counted as DLC - so you only add 1 game to your Steam library. Also IIRC only 1 key
- They are all DRM free ROMs, and can be used in another emulator if you prefer. I loaded mine on my Raspberry Pi