How can you tell the differentces of Sonic 1 North America, Japan, and another Japanise Sonic 1?
Sonic 1 US was the first release of the game in June. The Japanese game came out in July, and Sonic Team was able to tweak it a little. The big differences in JP Sonic are extra scrolling effects in most of the Zones.

  • Green Hill has scrolling clouds that move against Sonic on their own
  • Marble has scrolling backgrounds(the ruins and grass move with Sonic) and clouds that move with Sonic
  • Spring Yard has the same things
  • Labyrinth has rippling water effects
  • Starlight is unchanged
  • Scrap Brain has clouds that scroll with Sonic
  • I don't know if there's a second JP Sonic 1, Sega had an ad that named the game SegaSonic the Hedgehog but I don't think the name changed on the product itself.

    ~ SA Tails