Sonic-Tropolis is a game for the Wii U. The game is made by Taco Shell. Very much like the 2006 game Sonic the Hedgehog, the game is split up into many stories.
Sonic is at the S.E.G.A. (Secret Extraordinary Government Agency) trying to escape. He sees dark-colored Chaos Emeralds that are flying around him. He falls into a deep sleep, waking up on a mysterious island. He sees a map that says the island is called 'Paradise Island'. He tries to run off the island but is surrounded by water. He digs a hole underground where he meets the Undergrounders. The Undergrounders make Sonic choose a path: The Dark Path or the Ultra Path. If he chooses the Dark Path, he will go to Shadow's story. If he chooses the Ultra Path, then he will go have to run through, avoiding the spikes and Undergroundians, who are evil Undergrounders. He eventually is told by the Undergrounders that the path will go on forever, and he sees a Dig-Machine, which transforms Sonic into a brown hedgehog. This form is known as Dive Sonic. The Undergrounders tell Sonic to go down. However, if choosing to go up, he will dive into the ocean starting Blaze's Story. If he does go down, King Under will tell Sonic that Paradise Island needs help, and that the prophecy says that a "Brown Hedgehog" will lead the Island to safety and their island will be destroyed without them on it. If choosing the Dark Path or going up instead of down, right after Sonic gets out, a missle will destroy the island and everyone will panic. If not, then Sonic says that he is a blue hedgehog and runs out. However, he ends up in the Never-Ending Tunnel again, but the machine is destroyed and Sonic loses his power. The Undergroundians carry him after getting to the checkpoint the third time, and they will bring him to a chamber. They hit an ON button, and Sonic is attached to the giant missle. The missle flies up and Sonic struggles to get out, and ends up back on Paradise Island, except it is destroyed. Sonic races up Palm Tower, and finds King Under on top of it knocked out. King Over comes and destroys the tower, making Sonic have to run down the Crumbling Tower with King Under in his hands. If he makes it, then King Under's Story is unlocked. However, it is impossible for Sonic to make it unless he goes back later in the game and knows the Ultra Boost. If he does not make it, then Sonic falls and awakens the Ky-S2 1.0, a machine that was supposively destroyed 200 years earlier. It tries to fight Sonic. If it is beaten, then it will reveal its Special Attack and accidentally hits King Over instead. Sonic tries to get King Under to safety, but the game pauses and goes backwards. You can see a few events that will happen later in the game.
Rogue is controlling a giant robot while Knuckles tries to destroy it as Super Knuckles (golden, not in the same form as in Sonic Heroes) but fails miserably. Rogue grabs the Chaos Emeralds and creates Dark-Colored Chaos Emeralds called Ultra Emeralds. They fly away and Rogue tries to go catch them. However, Knuckles gets in the robot and hits her to Scary Cove, a dark island. Bats and spiders come out of a cave. A giant spider is carrying a giant Chaos Emerald. Rogue chases it into the cave, and nothing appears. Bats will snuggle around Rogue. The spider will come back, and the Chaos Emerald creates the Chaos Spider. Rogue flies out and loses her energy and falls into the polluted sea. She tries to get out but can't until E-123 Omega comes and gets her out. E-123 Omega destroys the spider, but also the Chaos Emerald. Everything is suddenly black except for the heart on Rogue's chest. She goes through a path of spiders and finds out that the source of all lightness comes from the Chaos Emeralds. E-123 Omega eventually finds her again, and he cleans up the rest of the Chaos Emeralds becoming a giant golden robot known as E-123 Chaos. She must defeat her friend in a boss battle. Suddenly, he explodes but the Chaos Emerald is fixed. The light returns, and Sonic falls on the island but there are no more spiders or bats and the water is no longer polluted. Rogue realises he is asleep and runs away. The game fast forwards.
If Sonic takes the Dark Path, it will go backwards instead of forward. Shadow is at S.E.G.A. with Sonic, and tells him that they must watch out. The robot that Knuckles was in appears and accidentally falls on Sonic. Shadow saves him from falling into the Spikeball Pit. He instead brings him to Paradise Island and flies away back to S.E.G.A. Knuckles realises that Shadow is there, and chases him through S.E.G.A., thinking he knocked out Sonic. Shadow learns the Ultra Boost, which Sonic can now do if you go back to his story. Shadow fights the robot and if he wins, then Knuckles will pop out and punch Shadow to a Tiny Island. Shadow is put asleep for many years. The game switches back to the start screen and a random glove goes to options and switches the game to RESTART. However, the game does not actually restart. This story is continued in Shadow: True Speed.
After the game restarts, the glove will go back to the game. Sonic's, Rogue's, and Shadow's stories are not unlocked. Instead, the first one shown is "Blaze's Tutorial". The same thing happens if you go up as Dive Sonic instead of down. Blaze does not actually do a tutorial though. She teaches Sonic and Shadow how to fly. You play as Sonic for this part only. Blaze gets distracted and accidentally goes into the water, and Sonic and Shadow are closing their eues and are caught by members of S.E.G.A. They break out and try to escape. Back to Blaze, she is under the water which has been polluted. She loses her power of fire. A fish guide named Puffz the Teenage Pufferfish meets her and says that the only way to stop the pollution is to get all the Ultra Emeralds and destroy them. She goes through a sea level and eventually gets out of the water and sees Rogue falling into the water. When Rogue gets out, she goes into a cave. Once she gets out, Blaze notices everything is dark. After she sees a "glowing heart" fight a robot, she shoots fire up into the sky which makes the island be light again. Sonic lands on the island. She helps Sonic and wakes him up. She notices the water is not polluted anymore and Puffz thinks that Sonic is an enemy, so he reveals his true form as a Shark and fights Blaze. Sonic didn't notice that this happened though. After defeating the shark, the game will go back to the start screen again and "glitches" so all stories are unlocked except for King Under's.
The Great Finale
Back at Sonic's story, Sonic puts King Under underground. Blaze flies out of the water and notices Sonic again. She reminds him that they weren't done with the flying lesson. You can play as either Sonic or Blaze in this level. If you choose Blaze, then she will have to fly through the rings. If you choose Sonic, you have to do tricks in the air and try not to fall in the water. They will both land back where the game started, a place called Big City. Rogue flies into them and panics. She gives them the Ultra Emeralds and tells them to destroy them. However, King Over finds them and takes the Ultra Emeralds. He uses them to create Over Ultra, a super powerful version of himself. Knuckles comes and hits the Ultra Emeralds out of his hands, thinking they are the Chaos Emeralds. In the process, they all land on Sonic, Blaze, and Rogue and they become Ultra Sonic, Blaze, and Rogue. Their form is just brown versions of them, except a darker brown Sonic than Dive Sonic along with a yellow sheild around them. Once defeating Over Ultra as Rogue, Over Ultra grows even more powerful and heads over to Blaze. Over Ultra absorbs Rogue's heart, and becomes an Over Ultra with vampire wings and fangs. After Blaze defeats him, he absorbs Blaze's fire, and he becomes fiery with fire breath. Sonic is hit with fiery fangs and falls. King Under comes and knocks the fire and bat out of Over Ultra, reviving Blaze and Rogue. They go over to Sonic. They realise that Sonic is too weak. Sonic tells them that the only way to defeat him for good was if they had the Chaos Emeralds. Knuckles goes back to S.E.G.A. and a giant vault is holding the Chaos Emeralds. He types in the passcode MaRiA, which he knows because that was the last word that Shadow said before he fell and Dr. Eggman hit a big sign that said her name just so he wouldn't know the passcode. He quickly grabs the emeralds and revives Sonic, making Super Sonic, Super Blaze, and Super Rogue. You can switch who you are in this battle. To win, you must dodge all the space junk Over Ultra throws at you and when he becomes throws a giant Ultra Emerald at you, you need to destroy it using Blaze's fire, or Sonic's speed to make no energy flow by going around it. Rogue can also be helpful- Since she is the weakest, he will mostly throw the emeralds at her. Switch to Sonic or Blaze before the Emerald hits you. If the Emerald does hit you, his "force" will pull it back. After defeating him, Sonic helps Paradise Island after getting in the Dig-Machine again. Blaze and Sonic then are taught how to do some really good air-skills by Rogue. Paradise Island has three new holidays called "Sonic Day, Rogue Day, and Blaze Day".
The only way to get King Under's Story is by saving him after going back to Sonic's story at the end and saving him. King Under's Story again takes place on Paradise Island. The gameplay in this story different, as you must rebuild the tower in the first level, and go through ten stories challenging Undergroundians in mini-games. At the top of the tower, King Under will meet Sonic, Rogue, and Blaze again, this time trapped in a cage together. Dr. Eggman will be the boss and defeating him unlocks Sonic, Blaze, and Rogue in this story. At the end, an extra cutscene is shown where Shadow wakes up on the island and goes to Space in the past, where you can play the first level of Shadow: True Speed.