Full list of all 25 SEGA Genesis Classics achievements worth 1,000 gamerscore. It takes around 8-10 hours to unlock all of the achievements on Xbox One.
Shining Force - Reached Alterone
Toejam and Earl - Found the secret island
Sonic Spinball - Collected all 3 Chaos Emeralds
Streets of Rage - Got to the last boss without using a continue
Golden Axe Games - Collected 200 magic
10 Challenges completed
Shinobi 3 - Earnt a Shinobi bonus (complete a level without throwing a shuriken)
Streets of Rage 3 - Finished the game
Toejam and Earl - Danced the Hula
Space Harrier 2 - Reached a score of 5,000,000
Sonic 2 - Finished Emerald Hills with 5 lives
Shadow Dancer - Completed the first two stages without using magic
Played 50 games
Sonic The Hedgehog - Collected all 6 Chaos Emeralds
Sonic Games - Collected 500 rings
Golden Axe 3 - Maxed out your magic
Dynamite Headdy - Defeated the Robo Collector
Played 20 games
Alex Kidd - Won 50 Games of Rock, Paper, Scissors
Golden Axe 2- Killed 25 enemies by knocking them off the environment in a single play through
Columns - Gained a high score of at least 5000 on easy
Alien Soldier - Used 4 different weapon modes in one session
1 Challenge completed
Golden Axe - Used magic when no enemies are present
Complete all challenges