Sonic 2 Extreme spaces.ru is likely a ROM hack of Sonic 2 with a potential tie to a Russian-language website or community. Without more information, it's difficult to elaborate on its specific modifications. The addition of "spaces.ru" suggests a connection to a specific online location where this ROM might have been distributed or discussed.  As a fan-made modification, it doesn't represent an official Sega release, but it shows the global reach and enduring appeal of Sonic the Hedgehog 2.

Sonic 2 Extreme spaces.ru

Sonic 2 except the music goes as fast as you do