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 Team
The Saturn did not achieve the commercial success of the Genesis, so Sega focused its efforts on a new console, the Dreamcast, which debuted in Japan in 1998. The Dreamcast was seen as opportunity for Sonic Team to revisit the "Sonic" series, which had stalled in recent years. Sonic Team was originally creating a fully 3D "Sonic" game for the Saturn, but development moved to the Dreamcast to align with Sega's plans. Takashi Iizuka led the project; Iizuka had long wanted to create a "Sonic" role-playing video game and felt the Dreamcast was powerful enough to achieve his vision. The game became "Sonic Adventure", launched in 1998, which became the bestselling Dreamcast game.