Sonic the Hedgehog/Green Hill

This is the first zone of the game and the easiest of the six. This area is overflowing with trees, waterfalls, loop-de-loops and more.

Act 1

 * Jump and get the game's first three rings, then hop up to the short plateau and jump on the 10-ring monitor.
 * Kill the fast blue bee robot, Buzzbomber, as it speeds by to shoot you, then jump to the nearby tree to your right. It's barely visible, but there's a yellow spring hidden in the treetop. Hop on it and you'll shoot upward to five more rings.
 * Go forward past the fish jumping up out of the water and then jump in the top of the second tree past that bridge. You'll hit an invincibility monitor that's there but that you can't see that well.
 * Run forward until you reach a yellow spring opposite a cliff overhang. Jump to that area, but watch out - the cliff overhang crumbles underneath your feet, as do all others that look like this one.
 * Go past about two more of these falling edges until you reach a blue post. It will turn red when you run past it - it's a checkpoint. You'll start back at that point should you happen to die.
 * There are two paths here. For the first, run straight forward from that goal point. You'll go through the famous dizzying loop-de-loop that mesmerized gamers in the Genesis' formative months.
 * For the second path, follow the floating platforms up to a cliff.
 * If the first path was taken, Sonic rolls through a tunnel that takes a short break to make room for another checkpoint. Note that this is the only path that contains a checkpoint. You'll shoot up a natural half-pipe of sorts and get a couple of rings in a large trapezoidal formation.
 * If the second path was taken to the highest ledge, you'll be able to run off the platforms that lead Sonic down to the trapezoidal formation of rings, giving you the chance to collect most of them.
 * When you come down, there's a short way to go until you make the exit. If you have 50 rings or more when you get there, there will be a humongous ring above the sign and to its right. Jump into it as you pass the sign and you'll be taken to a rotating bonus stage where you can try for one of the six Chaos Emeralds. If you don't have fifty rings, pass on to the next act.

Act 2

 * Grab the rings hovering horizontally over the bridge and vertically over the spring, then take a detour to the left.
 * There are spikes to the left of that yellow spring, and if you control your jump right, you can sort of dive past them to a lower area holding twenty rings and a shield, which will allow you to take a hit without causing you to suffer any ring loss.
 * You're now in this bottom pit area (if you made it past the spikes, that is), and you have no apparent way to get out. To do so, start from up against the spikes (you won't get hurt by touching their sides) and run to the wall to the right, pressing before you get in front of it. If executed properly, you'll roll up into a ball and destroy the weak wall ahead of you, which opens up into a more expansive area where you can get an item box containing Power Sneakers.
 * After getting the Power Sneakers, ride the moving ledge above you to the waterfall with rings in front of it. Make your way to the half-pipe ahead, which plants you on a swinging ledge. Get the rings that are in the ledge's path and stop at the tree to the left for a shield if you've lost your other one.
 * Above a loop is a multitude of rings as well as a 1-Up item box. You should be able to reach them with a good amount of speed and a well-timed jump.
 * Some invincibility in a tree to the right will help you blow right through to a checkpoint, though bewaring hazards in this next spiky area is important, as Sonic can get trapped in the pits even with the help of invincibility. Proceed with caution, jumping on each narrow platform carefully until reaching the checkpoint.
 * The path will split in two once again. If in need of a shield, take a left off the cliff to the end of the lower area, then take the swinging platform to the right of the area. Past some more badniks is a spring that should be avoided and an item box containing rings.
 * If taking the upper path, simply run past the crumbling cliff and slide through the tunnel.
 * Go straight ahead from here until you reach the exit (and hopefully, another large ring).

Act 3

 * Hit the top of the second tree from underneath to reveal invincibility, then speed ahead with it.
 * Use the spring to get up to the cliff edge that falls under Sonic's weight and keep progressing up the high road to a shield.
 * Try to stay along this high road until you make a checkpoint.
 * You have two choices here; get the Power Sneakers and speed ahead for a load of rings, or take the high road along the moving platforms and make it to another quick checkpoint. The high road reaps an eventual convenient reward, so take it.
 * When you make the second checkpoint post, ride along the moving ledges until you get to one that just falls. Let it take you down; you'll be on top of a loop-de-loop and right near an accessible 1-Up (the small reward mentioned earlier).
 * Jump down to the left to get a shield out of the palm tree below, then continue through the loop as normal and jump when you reach a small mound in front of the red springboard on the rock to get back on higher ground.
 * Ride the swinging ledge that stops in front of a series of ledges that fall shortly after you land on them. Jump across them to a cliff, above which is more invincibility.
 * Grab the invincibility and run with reckless abandon across the rotating spike log, which normally requires patience and good timing to get past.
 * Continue forward to the platform on a chain swinging very low over a bed of spikes. You'll come to a short curve that will result in you uncovering a 10-ring monitor. Shortly after that, if you get a running start from way back near the bed of spikes and jump at the correct moment, you'll get your third invincibility of the level out of a very tall palm tree. This comes just in time for your first battle with Dr. Robotnik.

Act 3 Battle
Here, you are introduced to the main villain of the Sonic series, Dr. Ivo Robotnik (often referred to as Dr. Eggman by Sonic and co.) You are given two platforms to attack Robotnik from (one on the left and one on the right.) Immediately stand on the right platform upon entering the area. When Robotnik enters from the right, begin attacking him before he pulls out his swinging weapon. When the pendulum comes towards you, jump through the small space between the ball and the main machine and head for the other platform to attack Robotnik. Eventually, the machine will be destroyed and you will be free to release the animals trapped in the nearby machine.