Sonic Jam
"Sonic Jam" is a compilation which contains the four main "Sonic the Hedgehog" games released on the Sega Genesis: "Sonic the Hedgehog", "Sonic the Hedgehog 2", "Sonic the Hedgehog 3", and "Sonic & Knuckles". Unlike future "Sonic" collections, "Sonic Jam" does not use a Genesis emulator; the games are proper ports, and all are nearly identical to the original Sega Genesis releases, with the exception of minor bug fixes. "Sonic Jam" emulates "Sonic & Knuckles" "lock-on technology"—a special feature that allows the player to merge elements of "Sonic & Knuckles" into previous games, resulting in changes to the level design as well as the choice to play as Knuckles the Echidna in "Sonic the Hedgehog 2" and Tails in "Sonic & Knuckles".
Sonic Generations
Sonic Generations is a 2011 platform video game developed by Sonic Team and published by Sega for the PlayStation 3, Xbox 360, Nintendo 3DS, and Microsoft Windows. An installment in the "Sonic the Hedgehog" series, the game—which was produced in commemoration of its twentieth anniversary—follows Sonic and his sidekick Tails as they form an alliance with their past selves to stop an evil entity from erasing all time. It features two gameplay styles: "Classic", which plays from a side-scrolling perspective like that of the original Sega Genesis "Sonic" games, and "Modern", 3D levels similar to those in "Sonic Unleashed" and "Sonic Colors".