Due to an increase in RAM, Sonic 2 manages a few features its predecessor had to sacrifice. Lost Rings, for instance, can be retrieved this time, but they must be recovered quickly because if they roll off the screen for even a second, they're gone. Sonic begins the game with 3 lives. Additional lives can be earned by popping open Item Boxes or collecting 100 Rings in any Act. (Continues, worth a full set of 3 lives, are earned with each Chaos Emerald acquired.) Sonic's got his usual crop of moves, once again sans the ability to push:

	walk -- Push left or right on the D-pad to initiate Sonic's movement in either direction. As you hold the button down, Sonic gains speed.
	run -- Begin walking and hold down the button to make Sonic gain speed. After a few seconds, he'll break into a run.
	screech -- While running, quickly press and hold the opposite direction on the D-pad to make Sonic screech to a halt. He'll skid for a short distance, based on how fast he was moving.
	look up -- While standing still, press up on the D-pad to make Sonic gaze to the heavens. As you hold up, the camera pans upward, giving you a view of Sonic's overhead surroundings.
	crouch -- While standing still, press down on the D-pad to make Sonic sniff his crotch. As you hold down, the camera pans downward, giving you a view of the stage beneath where Sonic stands.
	spin (回転) -- While moving, press down on the D-pad to make Sonic curl into a rolling attack. He'll remain in this position until you jump or slow down. The speed of Sonic's movement while in spin form is based on how fast you're moving when you launch it, and also on the terrain Sonic rolls along.
	spin jump (回転ジャンプ) -- Press 1 or 2 at any time to make Sonic leap into the air with a spin attack. The height of the jump is proportional to how long you hold the button down.

   The list of interactive items hasn't changed much from the original:

	Ring (リング) -- As long as Sonic has some of these, he won't lose a life if he takes damage. You get an extra life for every 100 you collect, but the count is reset to 0 in exchange. Each Ring is worth 100 points at the end-of-Act score tally.
	Item Box (アイテムボックス) -- In each stage, you'll find a number of these power-up bearing monitors. Pop them open with a spin to procure one of four power-ups: Big 10 Ring (ビッグ10リング) - Worth 10 Rings High Speed (ハイスピード) - Temporary speed increase Muteki (無敵) - Temporary invincibility 1up - Gives Sonic an extra chance
	spring -- Leap onto the broad side to catapult Sonic into the air. The springs are different colors in each stage, but they all have the same strength.
	spikes -- Like springs, spikes are different colors in each stage, but they're never something you want to touch.
	air bubbles -- Large, oxygen-filled bubbles periodically rise from these clusters: tag one to fill Sonic's lungs with air and prolong the time you can spend underwater. Some bubbles are strong enough to carry Sonic to the surface.
	Chaos Emerald (カオスエメラルド) -- As with Sonic 1, the Chaos Emeralds are lying right out in the open. The tricky part is finding them, as they're usually lying around on some remote, isolated platform that requires careful maneuvering to reach. There's one Emerald in each of the first 5 Zones, and the 6th is won after defeating Mecha Sonic. Collect all 6 to access the final stage, Crystal Egg Zone. Additionally, you're rewarded with a Continue for each Emerald you collect.
	Bonus Plate (ボーナスプレート) -- These signs can be found at the end of each first and second Act. Cross them to end the stage. You get a bonus depending on what's on the sign's face when it stops spinning: Eggman (nothing), Ring (worth 10 Rings), Sonic (1up), or Tails (Continue).
	capsule -- These are found at the end of each third Act, after defeating the boss. Jump into the rapidly vibrating UFO to bust it open and free the helpless animals within.

   Eggman's new crop of baddies are almost all based on designs from the original with swapped color palettes. Here's what he's got up his sleeve:

	Taraban (タラバン) -- Crab bots based on Gani-gani. They move back and forth along the ground, pausing every once in a while to fire flashing projectiles in either direction. ("Tarabagani" is Japanese for king crab.)
	New Motora (ニュー・モトラ) -- Beetle bots based on Motora. They roll innocuously along the ground.
	Meleon (メレオン) -- Meleon returns to do what he does best: hang around being invisible until Sonic approaches. The robo chameleon will appear just long enough to fire a flashing projectile.
	Game-game (ガメガメ) -- Turtle bots that quickly turn into spinning blades of doom as soon as they're approached. They fly off toward Sonic like frisbees. ("Kame" is Japanese for turtle.)
	Zaririn (ザリリン) -- Crayfish bots that float around underwater and charge at approaching hedgehogs. ("Zarigani" is Japanese for crayfish.)
	Drillin (ドリリン) -- Mole bots based on Mogurin. They roll back and forth along the ground, but when Sonic approaches, they turn into jumping fools.
	Buton (ブートン) -- Pig bots based on Ton-ton. They don't toss balls anymore, but they are capable of movement, hopping along the ground. ("Buu" is Japanese for oink.)
	Bomb (ボム) -- They're bigger than they used to be, but their attack patterns are the same: as soon as Sonic approaches, they explode into a shower of flashing projectiles.
	??? -- Fish bots that "swim" slowly through the air, usually in small schools of 2 or 3.

   There are seven Zones in total, each with three Acts. The third Act is nothing more than a short course followed by the boss. This time, you don't fight Eggman himself until the very end: the Zone bosses are some of his meaner robot cronies. As before, bosses must be fought without the luxury of Rings.

Under Ground Zone -- You can save time by hitching a ride on the mine carts, but stay on your toes because they like to hurl you straight into boiling lava. While in a cart, press down on the D-pad to duck (there is not actually any reason to do this). The Chaos Emerald can be found in Act 2, on a high platform above the exit. Arijigoku Mecha (アリジゴクメカ) -- Sonic rather carelessly flings himself into certain magma doom, but is rescued at the last second by, of all people, Dr. Eggman, who has decided he'd rather see his long-time enemy squashed by his latest creation than fried to death by natural causes. The lame-ass ant lion head, however, is nothing to be proud of. You don't actually get to fight the crummy contraption and he doesn't do much to attack - the only obstacle are the boulders bouncing down from the left side of the screen. Some bounce short and should be jumped over, some bounce high and should be walked under. Don't get hit and the boulders will smack into the ant lion. After 8 hits, Eggman will fly down and destroy it himself, his second stupid move of the day. ("Arijigoku" is Japanese for ant lion.)

Sky High Zone -- Looks alot like Hill Top, except criminally frustrating. Run into a hang glider to latch on. While gliding, press up on the D-pad to catch the wind and down to descend. Press 1 or 2 at any time to jump off. Act 1 is bright and sunny, but Act 2 takes place in a thunderstorm. The Chaos Emerald is way up in the clouds near the end of Act 2, and can be reached by springing through a series of cumulus platforms. Gachou Mecha (ガチョウメカ) -- This boss is fought in two phases. In round 1, all you have to do is bop a series of pissant little chick bots. Destroy the egg-shaped generators producing the chicks to lure a creepy goose head onto the scene. The goose will bob back and forth, firing flashing projectiles. ("Gachou" is Japanese for goose.)

Aqua Lake Zone -- You can skip along the surface of the water if you hit it with enough speed. In addition to the normal bubbles that replenish Sonic's oxygen, you can climb inside giant bubbles for a lift upward. In the last pipe near the end of Act 2, hold left on the D-pad to zip down a branching chute that will lead you to the Chaos Emerald. Mecha Ashika (メカアシカ) -- The sea lion is not so easy to hit. Jump on him at any normal time and he'll catch Sonic on his nose and bounce him around like a ball. Every once in a while the Seaworld rogue pauses to blow a balloon: jump on it to make it pop in the seal's face, inflicting damage in the process. ("Ashika" is Japanese for sea lion.)

Green Hills Zone -- This pastoral meadow is very straightforward, but oncoming obstacles are difficult to see in time. The Chaos Emerald lies on a high ledge near the end of Act 2, but can only be reached by blind spring-hopping from a platform about halfway through the stage. (BGM is based on "You Can Do Anything", the Sonic CD opening theme.) Mecha Buta (メカブタ) -- The sumo pig rolls or leaps from one side of the arena to the other... you can't damage him while he's moving, so you have to anticipate his course of action. At either end, he'll pause to do that sumo stomp thing, which is your only chance to attack. ("Buta" is Japanese for pig.)

Gimmick Mt. Zone -- Hovering platforms move in long, winding patterns, so keep an eye on your surroundings when hitching a ride. The Chaos Emerald lies near the beginning of Act 2: just after you climb up the first long slope, avoid the Drillin and leap toward the left just above the spikes. There's a trick wall that you'll leap right through, followed by a short obstacle course leading to the Emerald. Inobuta Mecha (イノブタメカ) -- The boar-hammer thing is stupid as a brick and simply charges from one side of the arena to the other. Don't try to hit him while he's on the move, because the spikes on his back will get you first. After he slams into a wall, he momentarily blacks out: this is your only chance to attack. Be careful, though, because the tremors from the impact cause debris to fall from the top of the screen. ("Inoshishi" is Japanese for wild boar.)

Scrambled Egg Zone -- This dark, craggy mountain forms a labyrinth of pipes. Act 2 is loaded with cheap hits, so you may want to pop an Advil or two before tackling this stage. There are no Chaos Emeralds to be found. Mecha Sonic (メカソニック) -- Mecha Sonic flies from one end of the arena to the other, occasionally pausing to probe his organic counterpart with a disturbing giant arm that extends from his stomach. Mecha can also spin into a ball, and when you spin into each other at the same time, both real and robot Sonic get knocked back without taking damage. If you've already collected the other five Chaos Emeralds in the previous stages, Mecha Sonic will relinquish the sixth to you upon his defeat. If you don't have the other five Emeralds, the game ends here and you get the bad ending.

Crystal Egg Zone -- This pastel castle of crystal is quite a switch from Eggman's usual grimy gunmetal hangouts, and it's probably best not to speculate what sort of urges drove him to seek refuge in such a distinctly feminine environment. Don't trust everything you see, because the walls here often conceal hidden passageways. Boss: Eggman, as per usual, hangs out at the right side of the arena. He attacks by shooting weird flower-shaped projectiles that oscillate and collect in the middle of the screen. At regular intervals, the entire background flashes with electricity: the only way to avoid this attack is to hop into the pipe that surrounds the arena. Defeat Eggman to free Tails and get the good ending.

• Master System: While the console is booting up, hold +1+2 on controller 2. Continue holding until the title screen appears, then press button 2 on controller one.
• Game Gear: While powering on, press and hold +1+2. Continue holding until the title screen appears. On Tails' third blink, quickly press START while still holding the three buttons. You should hear a Ring chime.