Sonic the Hedgehog 2: Master Edition 3 Extra Mode is a ROM hack or fan-made modification that enhances the original Sonic the Hedgehog 2 for Sega Genesis. The additions of the Master Edition and Extra Mode suggest the inclusion of extra levels, modified gameplay, and potentially new challenges not present in the original game. The game's foundation is still Sega's Sonic the Hedgehog 2, but this hack adds to the experience, showcasing the community's creative efforts in extending the game's content. It is not officially produced by Sega but created by independent developers.

Sonic the Hedgehog 2: Master Edition 3 Extra Mode (Time Attack)

Sonic The Hedgehog 2 RMS Edition V0.3