This game is NOT from the main-series, it's actually a spin-off, although it stars Sonic the Hedgehog characters.
Here's what happens in the Hero's Story. (see below)
The story begins when five shooting stars crash into the planet, one crashes into the Crimson Tower and rolls into the back of a MeteorTech robot. It wakes up, along with others and goes on a rampage.
The next day, Team Sonic are on their way to Megalo Station when they hear about the news on the radio. Tails gives Sonic a meteor which he thinks might be from last night. Sonic puts it around his wrist. Soon, they are attacked by the robots, who seem to have recognized the meteor Sonic is holding from last night, and barely escape with their lives. While Tails and Knuckles use their respective flying and gliding abilities to save themselves, Sonic almost falls to his death, but fortunately, the Ark of the Cosmos' was able to save him. All three then manage to escape from the city.
Team Sonic then meet up with Amy, who says she was being pursued by the robots, as well. As she hugs Sonic, she drops an Ark of the Cosmos. Tails then realizes that the robots are after the meteorites. They decide to go to MeteorTech to solve this mystery.
The team then arrives at MeteorTech and are greeted by the Babylon Rogues. Jet tries to force Amy to hand over the Ark but she is clueless as to what Jet is talking about. An alarm then sounds alerting the robots. Sonic and friends take off leaving the Rogues in pursuit. Sonic and Jet unknowingly crash into Eggman in the main computer room of MeteorTech. When he gets up and reveals himself, Sonic and Knuckles threaten Eggman and find out that he owns MeteorTech. When he sees Sonic's Ark of the Cosmos, Eggman reveals that his Mother Computer hasn't been responding ever since he gave it an Ark, which is why the robots are going out of control. He also says that the robot leader contains an ark. Jet remembers what he was there for but sees that Amy and Storm are missing. Eggman's computer shows that Storm is chasing Amy but they are being followed by the MeteorTech robot's leader.
Sonic, Tails, and Knuckles leave and find Amy in the Aquatic Capital. She informs them that the robot self-destructed and Storm ran off with something it dropped. She then says that Storm was going on about something he found in a place called Giga or something. Knuckles then confirms it to be the Gigan Rocks, a famous ruin among treasure hunters. The team arrives at the rocks and find the treasure gone. When Knuckles reads an ancient script, they find that Babylon Garden is a spaceship powered by the Arks of the Cosmos and that a great darkness assaulted it. Eggman then flies over with The Babylon Rogues's airship in pursuit. Sonic then says that they should catch up.
They arrive at MeteorTech's home tower and find Jet and the Rogues waiting. Wave confirms that Crimson Tower is MeteorTech's signal tower. Storm then says that the Arks they collected were stolen by Eggman. Jet challenges Sonic with the prize being the Arks of the Cosmos and Title of Fastest Creature in the Universe to whoever nabs Eggman first.
When they reach the top, Sonic and Jet enter at the same time and grab one of the two Arks he was holding. After bumping into his machine, Wave grabs the master Ark that fell out. After this, all robot operations are shut down. Due to the five Arks being in the same place at once, it called down Babylon Garden. Seeing that he doesn't need the Arks of the Cosmos, Sonic hands all of them over to Jet. When Jet accuses Sonic of running away, Sonic states that he'll see Jet at the next World Grand Prix.
Here's what happens in the Babylon Story. (see below)
The story begins in The Gigan Rocks when the Babylon Rogues are trying to get an Ark of the Cosmos at the Chalice. The Ark was held in a booby trap, so Jet punched in some keys on an ancient keyboard in Babylonian text. This deactivated the trap. Slowly, Jet grabbed the Ark of the Cosmos. No sooner than that, Wave saw a shooting star. There, she closed her eyes and put her hands together, making a wish. When she tells Storm what she's doing, he simply laughed, but not for long, as he saw Jet doing the same thing. Jet wished of having a power to beat "him". Then, three more crashed down and caused a rumbling sound just as Storm was about to make a wish himself. This re-activated the trap, causing two boulders to come crashing down. It nearly crushed them until the Ark's power caused them to fly out of the way. Jet remarks that "it looks like my (Jet) wish already came true". With this power, the Rogues escaped the ruin safely.
Back on the ship, Wave was analyzing the Ark of the Cosmos they found and explained it can charge up gravity and convert it to power the engine unit of Babylon Garden. She explains that there are five of them. Jet then orders her to create a radar to help find them. But before she could do that, Storm bursts in and shows a news report of a MeteorTech Mech stealing an Ark of the Cosmos from the Megalo City Museum. At seeing this, they set a course for Megalo City. After going through Megalo City, Jet tracks the robot to the Botanical Kingdom where he destroys the robot, but loses the Ark. He searches the ground and discovers Sonic talking with the others. When Amy hugs Sonic, the Ark of the Cosmos she found (the one Jet is after) falls out. Overhearing their conversation about MeteorTech, Wave and Storm appear and Wave suggests that they go ahead of Sonic and the others to gather information on MeteorTech.
They meet Sonic and friends at MeteorTech but are cut short by guard robots. As Sonic, Tails, Knuckles, Jet, and Wave ride off, Storm attempts to get the Ark of the Cosmos from Amy, only to get whacked by Amy's hammer. She then escapes with Storm in pursuit. They reach the Aquatic Capital and Amy throws the Ark at Storm's face. She then insists that he find away out when they are confronted by MeteorTech Robot SCR-HD. After scanning Storm's Ark of the Cosmos, it blows up and reveals a second Ark. Storm runs off with both Arks and returns to the airship. Jet, happy that they now have three, is cut off by Wave's description of an ancient Babylonian text. After Jet gives up on trying to figure out what the 'lightless black' is, he find that the two Arks are missing. Eggman then appears outside flying away with them, having snuck inside while the Rouges were determining what to do.
They follow Eggman to the Crimson Tower where they wait for Sonic and the others. Jet then challenges Sonic and they reach the top of the tower. After Babylon Garden is called down, the damaged SCR-HD breaks in and steals all five Arks of the Cosmos from Wave. Tails informs Sonic that the five Arks will make a giant black hole if put in Babylon Garden. After that, Eggman declares that massive energy readings are coming from Babylon Garden. A scene then shows the outer part of Babylon Garden falling off transforming it into Astral Babylon, the Babylonian spaceship and creating a black hole. Sonic, Jet, and everyone (except Eggman and Amy) rush to Astral Babylon's Mobius Strip to face SCR-HD's giant new form and disconnect the Arks of the Cosmos from the ship.
Afterward, it shows Astral Babylon orbiting Earth. Jet and the Rogues are atop a rock in the desert looking at it. After a quick conversation they fly off on their gear. The scene then switches to Sonic, Tails, Knuckles, and Amy, in Tails's car driving through Megalo City. Tails explains how the ancient Babylonians warped to Earth and left their engine unit in orbit. Then Amy theorizes that's probably why people started wishing on shooting stars. Shortly after, Sonic hears someone say his name in the tunnel. Jet rides up imposing a challenge. The scene ends with Sonic and Jet racing through the tunnel marking the end of the story."
Here's what the gameplay's like.
This game introduces new abilities most characters use throughout the entire game. By gaining gravity points through tricks and technical challenges, players will enter a zero-gravity zone and be able to perform two new moves: Gravity Dive, which sucks the player towards a black hole further down the track, giving them a speed boost which tosses cars and other objects off the track and into the air which characters are able to smash into to gain more speed; in the Wii version this move is done by flicking the Wii Remote upward (L or R trigger for using the Nintendo Gamecube controller) and in the PS2 version, this is done by pressing the R1 button; and Gravity Control, which changes the gravity of the course, allowing the player to use a different track, such as one of the walls. This is done by pressing the 1 button and tilting the Wii Remote in the direction you want to go (B trigger if the Wii Remote is in vertical position), by pressing the square button while tilting the left analog stick in the direction you want to go (PS2), or the B button and tilting the analog stick in the direction you want to go for the GCN Controller. (This move is very similar to "Chaos Control.") Also in the game is a move called Gravity Drift. This move is similar to the Grip move in Sonic Riders in which it can help characters turn on tight corners. This is also done with the aforementioned controls for Gravity Control. Items, first seen in the original Sonic Riders, give you special features, such as 5-30 rings, more gravity points, and an attack boost, which allows you to access shortcuts, such as springs. Item boxes can work against you, such as a ball-and-chain that hooks on your gear and slows your speed down. There are two special items that appear hidden in each course that will give you either 100 rings or 150 Gravity Points.
Along with the returning characters from the previous installment comes new items such as new playable racers, hover boards, bikes, air riders, yachts, air skates and other futuristic hover crafts that are available. These vehicles can be upgraded, even in the middle of a race. The PS2 version uses a Dualshock 2 controller while the Wii version supports 3 control methods: the Wii Remote sideways, the Wii Remote held vertically, and the Nintendo GameCube controller.
Here's a little something that is new in the Sonic Riders series. (see below)
There is a new method in the game called "Gear Change". Once you gain a certain amount of rings, you will get an opportunity to upgrade their gear. Each gear has from zero to three upgrades and can be upgraded during a race using the A button (Wii Remote), the Y button (GCN Controller), or the triangle button (PS2). Some upgrades include modifying your Extreme Gear's look, higher top speed, an increased Gravity Points Gauge, and character type specific upgrades, such as the ability to grind in rails as a Speed character, transform your Gear into an air ride/yacht-type to fly through Dash Rings scattered throughout the stage as a Fly character, or transform your Gear into an invincible bike/wheel-type as a Power character.
There are many different gear types:
- Board Style: A basic gear type that most characters can ride.
- Skate Style: Air skates that always allow the user to grind.
- Air Ride Style: Allows user to fly through Dash Rings and soar through the skies.
- Bike Style: Allows characters to knock away heavy objects.
- Yacht Style: Allows the character to fly and draft an opponent (different from the first game, as you only run along the slipstream)
- Wheel Style: Allows you to destroy obstacles and handle turns easier but the gravity control dash is short.
Special Gear: There are 61 collectible gear pieces.
Here's some boards and junk.
- The Blue Star, Type J, Black Shot, Pink Rose, Flame Lance and Rhythm Machine are all speed type gear. Each of them has three gear changes including Max Speed Up, Grind ability, and GP Gauge up.
- The Shooting Star and Turbo Star are similar to the first six boards, except neither of them has a Max Speed Up gear change. The Turbo Star also has two Starting Speed Up gear changes in place of GP Gauge Up.
- The Faster and Fastest are similar to the first six boards, except neither of them has a GP Gauge Up gear change. The Fastest has two Max Speed Up gear changes.
- The Light Board has the same gear changes as the Shooting Star, but its stats are different.
- One gear is called the Rainbow, and is the only gear with unlimited gear changes and no rings added, from grind parts, to Air Ride, then to a Bike. However, it is the most expensive gear in the shop, with a cost of 9999 rings.
- Although there is one gear supposedly similar to this gear, called the "Omnitempus", but it cost rings for gear changes, and it is not unlimited.
- One board is called the Gambler. It can multiply a player's ring count if the player comes in 1st in a race. Its gear changes are Ring Cap Up (50) and Ring Cap up (100).
- Another board is called The Crazy. This board uses rings as fuel, and it looks like the Crazy Taxi. Its gear changes are Ring Cap Up and Magnetic Barrier.
- Sonic has a second exclusive board, the Chaos Emerald. Just like The Crazy, this board uses rings as fuel. Using this board, Sonic can turn into Super Sonic with one Ring. Its gear changes are two Ring Cap Ups and Magnetic Barrier. After getting 50 rings, Super Sonic can use a Speed Boost that uses up rings twice as fast.
- The Rail Linker is an automatic grinder. Linking rail grinding is done automatically by this gear. Its gear changes are Max Speed Up, Starting Speed Up, and GP Gauge Up.
- One gear is called Wanted. If the player finishes a race without taking damage, the ring count will be multiplied. Its gear changes are exactly like the Gambler."
- "The Yellow Tail, Type W, Temptation, Smile, Psychic Wave and Night Sky are all flying type gear. Each of them has three gear changes including Max Speed Up, Air Ride, and GP Gauge up.
- There is a gear called the Airship. It has the same gear changes as the first six boards, except it transforms into a yacht instead of an air rider.
- There is a yacht called the Bingo Star. If a player gets three identical trick ranks in a row, many rings will be earned. Its gear changes are exactly like the Gambler.
- The Wind Star can transform into a yacht and an air rider using the gear changes."
- "The Red Rock, Type S, E-Rider and Power Egg are all power type gear. Each of them has three gear changes including Max Speed Up, Bike Transform, and GP Gauge up.
- There is a gear called the Wheel Custom. It can transform into a wheel and increase staring speed & max speed using its gear changes.
- The Road Star can transform into a wheel and a bike using the gear changes.
- There is a gear called Hang-On. It has very high stats, but its only gear change is a BGM (background music) change.
- SCR-GP is a wheel, but it doesn't have any gear changes.
- SCR-HD likewise doesn't have any gear changes, but, despite being a wheel, it can only take flying shortcuts as it is unable to take any power shortcuts."
"In Sonic Riders: Zero Gravity, there are three new modes, along with the main story mode: Survival Mode, Survival Relay, and Survival Ball. Survival Mode entails each player to use gravity in certain spots of the level to slam objects into opponents. Survival Ball mode is, simply put, a football game on Extreme Gear. Players score points by throwing a ball into a goal.But in the third zone,Megalo Junction, A noticeable change is made to the ball. It is the only ball that can explode and paralyze any player (including yourself) for several seconds. In Survival Relay, 2-4 players make a team of two and do a relay with a single Extreme Gear."
Here's some Courses and stuff.
"*Megalo Station, STORY-The story begins by the "metor" falling. Then Sonic, Knuckles and Tails are seen driving on a futuristic road toward Megalo Station. Tails is driving the car and telling Sonic about the meteor that fell last night. When suddenly MeteoTech robots burst out looking for them and causing a huge havoc. After escaping into a futuristic elevator, Tails had his suspicions about why the robots are on a rampage. When they got out of the elevator, they were assaulted by more MeteoTech robots causing them to crash through the wall and out into the open. Tails and Knuckles could keep up by flying. But Sonic couldn't fly, so he was falling, 300 stories to his doom, but suddenly the "stone" subtracted gravity and Sonic could float in the air. Sonic was surprised at what the stone did. Sonic was then playing with the "stone" for some fun. He then raced the MeteoTech robots in Megalo Station."OVERVIEW: "Like Metal City from Sonic Riders, this city is a futuristic city with many cars zooming about. The starting gate is in a futuristic train station that opens up to a freeway that has multiple branching paths, depending on the player's gear parts. The player could gravity dive straight through the freeway, ride along a wall, smash through a parking lot, ride in a car, grind on a rail, or use an air ride. No matter which path you choose, you will end up back at the train station." MUSICAL THEMES: "The music played in the level is entitled "Through Traffic". It has a fast-paced techno beat, best suited for racing in the advanced city."
*Nightside Rush, OVERVIEW: "The stage firsts starts at the same train station in Megalo Station. The race then eventually reaches an upside down track, probably assisted by the anti-gravity forces of the Ark of the Cosmos. The stage eventually returns to that same train station. The stage is practically the same as Megalo Station only that it's night and it's raining. There are shifting bridges which turn the stage upside down." MUSICAL THEMES: It's the same as Megalo Station.
*Botanical Kingdom, STORY: "After Sonic got away from the pursuing MeteorTech Robots, Tails came up with a plan which is to go to MeteorTech Premises themselves and see who is responsible behind all this. But guess which old friend they ran into? Yes, Amy Rose! She met them by shocking Sonic and saying "...guess who?", and she slowed the team down." OVERVIEW: This is another version of Splash Canyon, except that it has no water whatsoever and has a dome and floating plant pots.
The easiest way of finishing this course will be using a fly or grind character, although a daring way is also using Gravity Dive to dive until you reach the shortcuts. This could be very risky, however, remembering that there are plenty of areas where you can fall. Since this is an "almost-like-a-giant-ivy" plant with continuous roads and many holes, fly gears are the most effective here.
*Snowy Kingdom, STORY: "The Babylon Rogues are still trying to go through to MeteorTech in their "Ark of the Cosmos search" but they did not have much luck.The robot still had one Arc of the Cosmos and Jet tries to confront it.
Wave, after that, has to get out of this terrible snow-ridden botanical garden, because the snow is starting to turn to a mighty blizzard!" OVERVIEW: This level is the only one in the Sonic Riders collection that is set in an awful snow blizzard. Instead of racing, this level's point is for Wave to get out of here within the time limit and use her magnificent moves against the snow. MUSICAL THEMES: Same as Botanical Kingdom.
*MeteoTech Premises, STORY: "After reaching MeteoTech Premises, Sonic, Tails, Knuckles, and Amy spot a mass production of SCR-GP. Suddenly, they start to mobilize and Team Sonic believes they were spotted, but it turns out the units saw the Babylon Rogues. It was then revealed that the Babylon Rouges had one of the Ark of the Cosmos. Jet then states that Amy stole one of their Arks of the Cosmos, much to Amy's confusion. Sonic then states that "girls hate guys who rush them" and Jet once again proclaims that he's the fastest thing in the universe. But then an alarm goes off the the two teams (excluding Amy and Storm) race to the main office to find Eggman as the head of the company." MUSICAL THEMES: "The music played in this level is entitled "Gadget Round"."
*MeteoTech Sparkworks, MUSICAL THEMES: "The music that is played in this level is the same as MeteoTech Premises, "Gadget Round". The theme has a dance beat and a slightly heavy use of sound effects/synthesizers."
*Aquatic Capital, OVERVIEW: The race takes place in a waterworld. Gondolas appear frequently in the race. There are many Power-Type passage ways in the course.
Near the end of the course, there is a giant fountain in which the player can pass through by flying. MUSICAL THEMES: "The music played in this level is entitled "Aquatic Time". The theme sounds elegant and in a way: resembles the music for Empire City's daytime stage in Sonic Unleashed."
*Tempest Waterway, OVERVIEW: "The stage is similar to Aquatic Capital only harder and possibly in reverse, as the giant fountain from Aquatic Capital appears near the start of the course. The waters are much more rough due to the windy rainstorm making it harder for the player, and there are many obstacles along the way such as parked Gondolas and broken bridges. Near the end of the course, there is a building which looks like an abandoned water factory, where the player passes through a water slide. There are a couple shortcuts that can be taken when on-foot with the attack item that lead to a quick gondola ride, in which the player controls the direction of said gondola to collect rings, similar to Aquatic Capital's shortcut."
*Gigan Rocks, OVERVIEW: "These ancient ruins are built on and in a large mountain. The course starts with 2 large jumps, the first one having short cuts for every type leading off of it. After these jumps a turn leads to a cave, with yet another jump, that takes the racers inside the mountain. Once landing inside the mountain, there's a power short cut and the courses only attack shortcut. After a turn, go to a stretch of course that rises as the racers ride on it until it's going straight up (this is the best time to use gravity Dive). At the top of the stretch is another jump. The racers land out side near another power shortcut. There are also speed and flight shortcuts, but these can only be access if another character has created a slip stream. There's also another shortcut that can be access via a slipstream that can be used by any character type. After a turn, that can be avoided if the racer use any of the shortcuts, there's a quick stretch of land that leads to the finish line." MUSICAL THEMES: "The music played in this course is entitled "Sealed Ground". The music selection has an Oriental theme to it. It is also the first piece of Sonic music that incorporated the use of a didgeridoo."
*Gigan Device, STORY: "Team Babylon came all this way. For what? They're searching for the "Ark of the Cosmos", which is a legendary power stone in an ancient temple. They took it expertly, but they didn't count on one thing.
They set up the trap when they grabbed the stone almost carelessly. The boulder's falling on them! But wait, the Ark of the Cosmos held the boulder from falling! What a powerful stone..." MUSICAL THEMES: "The background music played in this level is entitled "Sealed Ground"
*Crimson Crater, OVERVIEW: "The race takes place in a mechanized city, specifically in a tall metal tower in the center of the city, where Eggman's mother computer is located. The player starts off from a tall ramp. The stage is rather difficult as it is the last stage of the Heroes Story." MUSICAL THEMES: "The music played in the level is entitled "Dive Into Gravity".
*Security Corridor, HINT: "The race track begins like any other- you back up and then cross the startline when the green line passes you. When you pass over the start line there is a shortcut in the vent that spins behind the jump. Otherwise you just keep following the paths and follow the signs until you reach another vent that is another shortcut that can help you win the race. When you get there gravity push yourself into it just like the first and follow the track. There is a lift off that you get gravity points when you hit the bottom but as soon as you lift off you gravity push yourself into yet another vent that you can use as another shortcut to end up sooner at the finish line." MUSICAL THEMES: It is the same as Crimson Crater.
*Astral Babylon, OVERVIEW: "The race takes place in the inside of the spaceship form of Babylon Garden. The course has only four turns. The player can hit panels to open new items or shortcuts such as a ramp for Fly-Type characters, a rail for the Speed-Type characters and objects for the Power-Type characters. Although there are no other shortcuts available, the player can use Gravity Control to break through the glass wall and go through the stage faster. Odd objects appear in the sky, possibly ancient Babylonian satellites or planes. Digital logos of Babylon and lights appear near the start of the course." MUSICAL THEMES: The music is the stage is called "The Core" same as in Mobius Strip.
*Mobius Strip,STORY: "One MeteorTech Robot stole all the Arks of the Cosmos! He has turned into a giant, powerful robot and the Babylon Garden is causing a black hole to appear which can consume the whole planet! Turn the Babylon Garden's core off and shut it down!" OVERVIEW: "This level is the only boss level which does not allow you to take control of your gravity actions since you don't have the Ark of the Cosmos. You (the player) are the only one that is fast enough to run through Master Core: ABIS and destroy him for good. This is a very simple track with almost no obstacles and only four jumps to build up Gravity Points. There is also a rail and flight pads for those with the right gear to use for more points.
As the players race along the level, Master Core: ABIS will try and attack the player. During the first lap, he will do nothing. The second lap has him hurling electric bolts that riders with Bike and Wheel Gear can knock back for Gravity Points. The third lap will have him forming large meteors and throwing them onto the track, creating explosions.
Twice per lap, Gravity Control automatically activates and hurls the player as usual. Using the lifted floor tiles, the player must grind to Master Core: ABIS and hit it before their Gravity Points wear off. Once he has been twice in one lap, the next one begins until the designated number of laps has passed and destroys the boss." MUSICAL THEMES: "The music played in this level is entitled "The Core".
*80's Boulevard, OVERVIEW: "The track starts in a street whose design is similar to Times Square, located in New York. As the player progresses throughout the stage, the track then branches into a 4-way crossing crowded with buses (which can be used for a gravity dive). It then transitions to a subway station where one can either take the opportunity to ride on top of a subway train or take the stairs, where rails are located. This area can be an advantage for speed characters."MUSICAL THEMES: "The theme for this stage is entitled "Blast Town". The song can be traced down to the 1980s, where fast, upbeat music flourished from disco parties and prom nights in high schools. The song is also used for the track 90's Boulevard."
*90's Boulevard, MUSICAL THEMES: "The music that is in this track is called "Blast Town". This song is also used in 80's Boulevard, and the song uses blaring trumpets along with banging drums to show the cultural "bang" of the 90's.""
Information from http://sonic.wikia.com/wiki/Sonic_Riders:_Zero_Gravity
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