Sonic The Hedgehog in the Fourth Dimension is a book released in 1993 and the second title written by the collective Pseudonym Martin Adams.
Sonic and Tails must prevent Dr. Robotnik, who has discovered a time machine, from changing the past, destroying the resistance and becoming supreme ruler on the planet Mobius. To help them traverse time they meet up with The Organizers, a group of extra-dimensional humans who guard the space-time continuum, who Robotnik had stolen his time machine from. They in turn help the Organizers fend off the Mythos creatures, a faction of mythological creatures fighting to gain a place in "reality", the dimension Sonic lives in, where logically they should not exist. The leader of the Mythos creatures, Arctur the Dragonkin, supplants Dr. Robotnik as the primary antagonist of this story.
Tropes used:
- Alternate Timeline: Several pop-up in the book, but the one that Sonic and Tails spend the largest amount of time in is the one where they prevent Dr. Kintobor from transforming into Dr. Robotnik. Another exists where Robotnik has already "won".
- Anachronism Stew: The pair travel back to the Cretaceous period to have fun with dinos, yet somehow meet a proto-hedgehog and fox; almost identical to Sonic and Tails.
- Artistic License – Paleontology: Utahraptors are apparently the size of a small skyscraper.
- Bad Future: Robotnik manages to succeed by by the first chapter of the book making Sonic and Tails set off to fix it.
- Beleaguered Bureaucrat: All the Organizers are hampered by their system but they do seem to genuinely care about protecting the universe.
- Canon Foreigner: Carrie the Coypu, Eric the Echidna and The Organizers.
- A Child Shall Lead Them: The Elders of the Fourth Dimension are led by a kid. She's actually sensible and reasonable, teenaged messiness aside.
- Clingy Costume: Several of the Mythos trick Sonic into putting one on which prevents any movement on voice activation, it can only be deactivated by somebody else but seemingly anybody else which means it's easy to get out of if somebody friendly finds you.
- Dare to Be Badass: With the Mythos creatures' time travelling rocket headed for the Big Bang, whereby, via the Chaos Emeralds, to rearrange the universe to their purposes, Sonic fears Kintobor's Time Travel-modified treadmill won't get Sonic and Tails there fast enough.Dr Kintobor: This is where you prove yourself, Sonic. Are you really the fastest living creature in existence, as you claim? Prove it. Get on that treadmill and run as if your life depended on it. Even if you don't succeed, you have to try.
- Delayed Ripple Effect: The climax of the book sees Sonic and Tails outrunning (literally, they're on a time-traveling treadmill) the blast of the corrupted big-bang traveling through time.
- Draconic Humanoid: The lead Mythos is Arctur the Dragonkin; a snake-like creature with arms and legs, and protrusions on the back of his costume that are suggested to be covering wings.
- Dressed All in Rubber: The Mythos are all dressed in form fitting rubber-like suits.
- Endless Corridor: Literally endless, the fourth dimension is nothing but rows and rows of corridors on-top of endless floors of similar looking corridors.
- Enemy Without: Sonic gets (another) alter-ego with Cinos; the reverse of Sonic which Tails fails to cure forcing Sonic to merge with it.
- Evil Gloating: With Tails captured, Sonic unable to damage his improved egg-o-matic and their only escape route destroyed what does Robotnik do? Oh yeah; gives a run down of his plans and how the two are doomed to non-existence. This of course gives Sonic time to escape his grasp.
- Evil Is Petty: Before trying to erase Sonic and Tails from existence, Robotnik alters history so Tails has a clingy girlfriend. Who is one of his robots. When he takes over Mobius, he uses clones of Sonic's friends as henchpeople.
- Evil Laugh: "Two things float in the air around him at all times: the horrible smell of rotten eggs, and a high-pitched chortling laugh which he will break into at a moment's notice."
- From Bad to Worse: As one of the time police notes, during their meeting with Sonic and Tails, Robotnik's managed to climb in threat level twice.
- Gaia's Lament: What the world looks like under Robotnik. The Green Hill Zone becomes what Sonic and Tails dub the Brown Hill Zone, covered in oil and smog. It actually manages to get worse after they're away.
- Hamster-Wheel Power: The time-travel device Sonic and Tails use near the end of the book is cobbled together using a treadmill as the power source. The faster the duo run the quicker they travel in time, this becomes a plot point.
- Hidden Elf Village: The planet Mobius is one, hidden by higher powers to stop people abusing its beautiful scenery. The Mobians don't know this.
- In Their Own Image: The time-travel plot of the Mythos Creatures, to make a home for them when the universe formerly didn't have the space or rules for them to exist. This book inspired the creation of that trope page.
- Invisibility Cloak: The Mythos ship has one; Sonic walks into it.
- Jerkass: Sonic has a few sudden, unwarranted mean thoughts towards Tails. Admittedly, Sonic's supposed to be an arrogant teenager, but they're pretty unfair all the same.
- Mecha-Mooks: Badniks.
- My Future Self and Me: At one point there are three Sonics and Tailses; at the end they trick Robotnik into beliving the whole dimension is populated by Sonic and Tails look-a-likes with this paradox.
- Necessary Fail: In order to save the universe Sonic must allow Dr. Robotnik to exist; so he can steal the Chaos Emeralds and thus prevent the Mythos from getting their hands on them.
- The Neutral Zone: One floor in the Fourth Dimension is set up as one.
- Never the Selves Shall Meet: It's not impossible, but multiple versions of one person in the same time are not a good thing; Sonic and Tails accidentally merge with past versions of themselves when they just touch each other, although Sonic is able to 'weaponise' this to stop Cinos (a version of him created when he was exposed to the same Chaos energy that turned Kintobor into Robotnik).
- One Nation Under Copyright: A sign of Robotnik's rule is that everyone and everything, right down to the individual rocks are branded with his copyright.
- Peace Conference: One happens at the end of the book; it's of course Sonic that manages to come up with the idea and force the two forces to talk to each other.
- Product Placement: At one point Sonic is playing on his "sleek" Game Gear.
- Ret-Gone: Robotnik mounts his first attack by erasing Porker Lewis, and later attempts to erase Sonic and Tails by going back to find and kill the first hedgehog and fox to evolve on Mobius (unable to just eliminate Sonic and Tails' parents as their orphan status meant that nobody knew who their parents were).
- Reset Button: The novel concludes with everything that happened erased and only Sonic and Tails remember everything.
- Ripple-Effect-Proof Memory: Questioned at one point- to the extent that Sonic and Tails remember the real history before they've even done any time-travelling themselves- but never really explained.
- San Dimas Time: At one point Dr. Robotnik claims the heroic duo only have fifteen minutes to exist, as his robots have found (and are about to kill) the first evolved hedgehog and fox on the planet.
- Sdrawkcab Alias: The book uses the Dr. Kintobor created Sonic and turned into Dr. Robotnik in a failed experiment as the back-story.
- And later in the book Sonic's reverse Cinos appears when a time-travelling Sonic is infected by Chaos energy, requiring another Sonic to merge with Cinos to stop him.
- Shout-Out:
- Sonic, a speedster, acquires a time-travelling treadmill. Sound familiar?
- Sonic bemoans an Alternate History Green Hill Zone cliff face to be "covered in oil and smeg".
- Super-Speed: It’s Sonic!
- Take a Number: Sonic and Co had to take one before meeting with the Science Council of the Organizers; with was up in the 4000s while the current number called was 24. Needless to say this didn't go down well with one impatient hedgehog.
- Temporal Abortion: After Robotnik gets his hands on a time machine, he starts eliminating all the heroes from existence by sending his robots back in time to kill their parents before they were born. He runs into trouble when he tries to do this to Sonic and Tails themselves, however, as they're both orphans whose real parents are unknown, so he has to send them back into prehistory to kill the first hedgehog and fox ever to evolve on Mobius (and then foolishly tells them about this, giving them the chance to go back themselves and save their ancestors).
- Time Police: The Organizers; who actually have a sub-division called the Time Police (they're not very good at their job).
- Time Travel: Key component of the plot.
- Victory Is Boring: After rewriting the timeline so Kinotobor doesn't become Robotnik, Sonic quickly becomes extremely bored.
