Title: Sonic the Hedgehog
Format: Megadrive (Genesis)
Developer: Sonic Team
Genre: Platform
Cart Size: 512kb (4Mbit)
Release Dates
Japan: 26th July 1991
Europe: June 1991
N. America: 23rd June 1991

Back in 1991, Sega had trouble holding onto the spotlight. The Megadrive lived under the shadow of the SNES and Super Mario World. What Sega needed was a Mario of its own. Sonic didn't have the quality of gameplay that Mario World had, but it certainly looked better. If you saw the two games running side-by-side, you'd think the Megadrive was the superior machine. It was also a lot of fun to play.

Story (from European & N. American instruction manuals):
Dr. Ivo Robotnik, the mad scientist, is snatching innocent animals and turning them into evil robots! Only one tough dude can put a stop to the demented scientist's fiendish scheme. It's Sonic, the real cool hedgehog with the spiked haircut and power sneakers that give him super speed.

Help Sonic fight hordes of metal maniacs and do the loop with the super sonic spin attack. Speed down twisting tunnels and swing over dangerous booby traps. Leap across lava pits and dodge burning rocks. Then splash through the chilling waters in an underground cavern. And if you're lucky, you can warp to the secret zone where you spin around in a floating maze! Your greatest challenge lurks in a secret lab where you come face to face with Dr. Robotnik himself!

Spin through space, loop 'til you're dizzy, save the animals and become the super hero. Be Sonic! Be atomic!

Story (from Japanese instruction manual):
The malevolent gifted scientist, Dr. Eggman, prepares his bad intentions again: "Sonic... This impertinent, this contrary hedgehog; he hopes that my bigger projects are always annihilated. But this time, my strength that resides in my intellect will crush him! Ha ha ha ha..."

South Island is a treasure of jewels and ruins, including the "Chaos Emeralds" that sleep buried somewhere within the island. These stones deal to all life a terrific energy. New techniques basing themselves on nuclear weapons and laser radii are then possible. But, they are not necessary should these stones fall between bad hands that don't understand their power. Also, since South Island is an island with a circular movement, the island started forming a interdimensional torsion in which the Chaos Emeralds wander.

One day, something horrible presented himself on the island. Dr. Eggman and his army set foot there. "Ha ha!. Even though it is necessary to transport every particle of this island, I will have the Chaos Emeralds!!". Then, Dr. Eggman undertook the development of an enormous fortress in an angle of the island.

"Eggman, not again him?!!! Hearing rumors circulating on South Island, Sonic ran. Dr. Eggman thinks that Sonic is his deadly enemy, but Sonic does not really account of his adversary. However when Sonic arrived on South Island, a strange spectacle was held before Sonic. "Look Sonic, this time the situation is totally different! ALL the animals of the island have been transformed into robots!"
"E... everybody!"
"These individuals act henceforth under my unique control. In short, all the island is now your enemy! Bwa ha ha ha ha ha.. This time, the whole world will be mine!"
Difficult! But go for it! As Sonic the Hedgehog, everybody waits for your help.

Translation by Mary Yamasaki

Green Hill Zone
Go around the giant loop, tumble down tunnels, and jump over crumbling cliffs before you get a chance to blink. Bounce on springboards but not on spikes.
Marble Zone
Leap across pools of red-hot lava and shifting islands. Then find the way to the underground palace where massive weights and flying balls of fire block your path.
Spring Yard Zone
Jump from springs and bounce off bumpers as if you're in a real pinball machine.
Labyrinth Zone
Explore an intricate maze filled with water. A countdown begins to let you know when you are running out of oxygen. Breathing air bubbles keeps you from drowning.
Star Light Zone
Speed through the stars like a roller coaster in a world that twists like a corkscrew.
Scrap Brain Zone
Slippery metal floors, razor-sharp saws and grinding wheels - now you're one step away from Dr. Robotnik's hideout.
Final Zone
Bizarrely, this is the easiest boss in the game. You can simply stand in the corner and hit Robotnik as he appears, then avoid the slow-moving ball things that fall from the ceiling.
Special Stage
If you collect a certain amount of rings, you can warp to the Secret Zone where you'll ricochet off multi-colored blocks in a 360-degree rotating maze.

Box cover
Manual cover
Box cover
Manual cover
N. American
Box covers
- Original
- Not for resale #1
- Not for resale #2
- Sega Classic re-release
Manual cover

After beating Robotnik, Sonic returns to Green Hill Zone where his little animal friends are dancing about. If you've collected all the Chaos Emeralds, you see an extra sequence where the Emeralds float into the air and disappear.
Hidden Staff Names Screen
There's a code that only works on a Japanese Megadrive (or an emulator set to Japan mode) which activates a screen showing the names of some of Sonic Team's staff. The same code also activates the "Press Start Button" thing on the title screen.
Outside the Special Stages
Using debug mode to leave the confines of a Special Stage will take you to a bizarre area filled with blue Chaos Emeralds and unused objects.
Labyrinth Zone Hidden Area
In act 1, the second switch you come to makes a hidden platform appear above the water. Climb back up to where the platform is (this can be a bit tricky) and use it to reach a hidden area.
Monitor and the Pink Thing
In Scrap Brain act 2, there's a monitor hidden inside a wall that, when smashed, makes a pink block rise out of the ground to the right of Sonic (see picture). The pink thing is actually a piece of an "electrified orb" with a different pallete.
Japanese Revisions 1 and 2
There are two additional versions of Sonic 1 which were only released in Japan. They feature some small graphical improvements and bug fixes.