Sonic the Hedgehog platforming of the main levels. The 16-bit "Sonic the Hedgehog " consisted of a giant rotating maze, which many considered a major technical achievement. The most common special stages, however, were segments with the character running through a long tunnel to collect certain items. 3D "collect item" levels, as in "Sonic 3" and "Sonic & Knuckles", used the same perspective but had Sonic collecting all the blue-colored orbs on the surface of a giant sphere. Finally, "Sonic Advance 2" employed a 3D ring-collecting stage, and "Sonic Chaos" ("Sonic and Tails" in Japan) used a variety of gimmicks for its levels.
Sonic the Hedgehog Pocket Adventure "Sonic the Hedgehog" games for the Sega Genesis. The game is heavily based on "Sonic the Hedgehog 2" (1992) for the Genesis, while also using concepts from "Sonic the Hedgehog" (1991) and "Sonic the Hedgehog 3" (1994). "Sonic 2"'s stage themes are featured throughout, but the stage layouts are unique to the game. The bonus stages are also borrowed from "Sonic 2". "AllGame" called the game "a slightly dumbed down port" of "Sonic 2" and "Official Dreamcast Magazine" called it "essentially an adaptation of "Sonic 2."" Unlike "Sonic 2", "Sonic Pocket Adventure" features some exclusive modes. The game includes a