The SA2 Tutorial
SA2 features a REALLY NICE tutorial available in the "Extra" menu at the main screen, and the background music is excellent, so I'd suggest using that. I'm going to concentrate on errata & notes for basic moves & undocumented advanced moves on this page.
Jump - Press A.
Action Menu - Press Y to change the current command on the "B" menu at the top of the screen. The single biggest design issue in SA2 is the messed-up handling of the action menu. There is a spiffy delayed slide-in effect on the menu. Unfortunately, when you have to do something fast, this means that you can't be 100% sure the X/B button will do what you want unless you wait for the menu to slide out, and in many cases you have to do the move before it does so. This is especially annoying when you need to light dash while running or in the air and when you're in the Chao Garden.
Pick - Press X/B near an object. You can be sure you'll pick up the object when "Pick" is on the action menu. Objects that you can pick up depend on the stage you're in and tend to be very small. Some objects have hidden animals under them that you can collect by picking up the ohject. Pick, Put, Hold , and Throw are all void when Tails and Eggman are in their mechs.
Put - X/B when holding an object.
Throw - X/B when walking/running and holding an object. Can be used to defeat enemies.
Whistle - X/B when standing next to a small white pipe, or, if you use the action menu, standing anywhere. Pipes always contain small animals, unless you've already used them. Whistling anywhere else in a level usually does nothing, but occasionally you can find an invisible animal if you do this. Whistling in a Chao garden will cause Chao that REALLY like your character to come running.
Sonic / Shadow
Homing Spin - Press A while jumping to home in on enemies and other objects. You can use this to hit multiple enemies before landing on the ground for extra bonus points. Be careful, as Sonic/Shadow don't spin through the entire Homing Spin, and doing it at long range can get you hit. Sometimes you'll jump
Somersault - Press X/B anywhere. This move lets you break containers and roll through small spaces. Unfortunately, you can also use it when there aren't any crates or small spaces around, so about half the time you'll somersault by accident and slow yourself down.
Spin-Dash - Hold X/B to charge.
Grind - Land on rails to slide.
Crouch - X/B on rails. Increases your speed on straight rails, but slows you down a ton on curves.
Tails / Eggman
Volkan Cannon - Press X/B to fire at crates or enemies.
Propeller Punch / Punch Glove - Press X/B when really close to items or enemies.
Targeting Laser & Homing Missiles - Hold X/B and move the laser over items & enemies. Some objects can also be targeted. The laser will only run for a while, so be sure to fire before it releases the targeting, although in some cases you will want to turn off the targeting on purpose. Release X/B to fire the missiles.
Tail Spin (Tails Only - Chao Garden) - Press X/B when action menu is off. Be careful not to do this, as it's really easy to get your Chao mad at you. Make sure the ction menu says what you want at all times.
Flying (Tails Only - Chao Garden) - Hold A in the air. This time, Tails' flying is really more of an unlimited hover.
Knuckles / Rouge
Glide - Hold A in the air.
Climb - Jump or Glide into a wall and use the Control Stick. The addition of regular jumpimg to climb is a major change from previous games and I keep jumping off when trying to glide in by instinct.
Drill Claw / Drill Dive - Press X/B in the air. This can be used to dig when you get the Shovel Claw / Pick Nails.
Punch / Kick - Press X/B. There are both standing and running versions. Doing this 3 times in a row will cause Knuckles / Rouge to do either a jump attack (standing) or a whirling attack (running).
You get 100 points for any enemy you defeat.
Unlike in previous games, rings don't affect your score, probably because A emblems would either be too easy or icredibly annoying if rings were counted in them.
You get a bonus for your stage time, but in SA2 the bonus seems to be a flat scale, while previous Sonic games gave you a set score for getting a certain range of times.
You get a bonus for doing certain tricks that depend on the character you're using. These bonuses are the key to the A emblems. SA2 takes a cue from Mario in that all characters can get bonuses by defeating multiple enemies in a sequence (either in 1 move or by staying off the ground with the Homing Spin).
Good! (Turquoise) - 100 Points
Nice! (Green) - 200 Points
Great! (Blue) - 300 Points
Jammin! (Yellow) - 400 Points
Cool! (Tinted Yellow) - 500 Points
Radical! (Yellow-Orange) - 600 Points
Tight! (Orange) - 800 Points
Awesome! (Deep Orange) - 1000 Points
Extreme! (Magenta) - 1500 Points
Perfect! (Rainbow) - 2000 Points
Tricks & Advanced Moves - Sonic / Shadow
You can add to your score in 2 ways - defeating enemies especially in a sequence) & using objects. You really have to know the stage well to get all the object bonu8ses, but there are certain things to look out for. A emblem scores for Sonic & Shadow range from 10,000 to 25,000, approximately.
Optional Objects - Everywhere - You can sometimes get bonuses by using objecyts that you don't have to use to finish the stage, but will involve a lot of style to use properly. Examples include optional grinding rails just about anywhere (you frequently have to grind at high speed to get the full bonus, so crouch). Another example is the bomb item monitor in Crazy Gadget, which will get you a "Cool" bonus if you get it or get close to it by bouncing off a floating spring enemy. Jumping on 3 ramps in succession and landing on the 3-spring battery in a certain area f City Escape will get a "Tight" bonus. Grabbing the high handle on the rocket in Metal Harbor instead of the low one will get you an "Extreme" bonus. You can get a bonus by going through or even touching the 3rd in the sequence of 3 closing doors in Pyramid Cave.
Ramps - City Escape & Radical Highway - Press A while running on a ramp. Depending on which ramp you use and how you use it, you can get a "Nice," "Cool," or "Awesome" bonus. Normal ramps always seem to give a "Nice," but when Sonic is on the "snowboard," hitting a ramp at high seed will give a "Cool" and hitting it at high speed and turning while jumping will give a "Awesome."
Jumping Rails - Final Rush & Sky Rail - Rails that have an upward bump at the end will give you a bonus and launch you in the air if you jump at that bump. It seems that you must land on ground and not another rail to get the bonus. At high speeds you get an "Awesome" bonus. In Final Rush, such rails are marked with a glowing green X. In Sky Rail, the first rail works that way and I believe there's 1 other rail with a bonus too.
Tricks & Advanced Moves - Tails / Eggman
All bonus scoring for Tails & Eggman seems to be based on enemies, but obviously, they can get some very large enemy bonuses. Be sure to target all bombs on a bomb robot and try moving around nnd holding the laser to include enemies i multiple rooms in the same bonus. Note that getting hit while firing will cancel your bonus. Bomb packs on posts count as enemies too. A emblem scores for Tails & Eggman range from 20,000 to 50,000, approximately.
Propeller Dash - Tails Only - Chao Garden - A cool quirk about Tails' flying in the Chao Garden is that he can hover more than once. Release the hover and quickly enter the command to hover. Tails will have a "forward" animation as long as you keep pushing in a direction. It looks like he's using his tails to go forward, like when he's running. Useless but interesting.
Tricks & Advanced Moves - Knuckles / Rouge
You can get bonuses from enemies and getting emeralds. The emerald bonus is based on the timer and how many hints you use. A emblem scores for Knuckles & Rouge range from 10,000 to 15,000, approximately.
Spiral Upprt / Screw Kick - Have you noticed that certain areas of Rouge's stages seem to be just barely out of jumping range? Well, there's an undocumented move that lets you reach them. Rotate the Control Stick and it will appear on the Action Menu, just press X/B. Use this to get the 1-UP in Dry Lagoon, for example.