You think you know this story? You don't.

Worlds collide when Dr. Eggman makes his way to the magical land of Equestria and forms an alliance with Allura the Leopard to gain the power of the Unity Crystals. Given this, two very different groups - led by Sonic the Hedgehog and Sunny Starscout respectively - must join forces to stop the villainous duo before Equestria is doomed.

A reboot of the Sonic x MLP: G5 Saga, taking place in a different universe.

This story is a sequel to A Perfect Pitch

Pipp and Hitch have been dating for two years now. Their relationship has made it through thick and thin—Opaline, Misty when she was evil, Allura, and the day to day life, but when a fight threatens their relationship, Hitch, as well as the rest of thier friends, begin to question if they really know Pipp at all....or at least this one.

Sequels:

Magic In Us:
https://www.fimfiction.net/story/560696/the-magic-in-us

Secrets of the North:
https://www.fimfiction.net/story/561815/secrets-of-the-north

A Trial of Secrets:
https://www.fimfiction.net/story/565208/a-trial-of-secrets

What if Spottedleaf was given a second chance at life just before her spirit faded away for good? Follow the former ThunderClan medicine cat as she finds her own place among ponies.

This story is a sequel to G5 Adventures in Scooby-Doo! Legend of the Phantosaur

Violette Rainbow is so excited to stay an entire weekend with the Mane 6 in the Crystal Brighthouse before school in Bridlewood starts that next week, but little does she know that she is being sent on a Unity Quest with the Mane 6 as well.

This time, they are transported to Fernfield, Washington, home of the legendary Golden Retriever athlete Air Bud, his wife Molly and his five adorable puppies (the hip-hoppin' B-Dawg, lovely RoseBud, mellow Buddha, dirt-loving MudBud, and the big fella Budderball), who share an incredible secret-- they can talk, but only to other animals and ponies.

When it comes time to adopt the young puppies into new families, humans, ponies and dogs alike are distraught and Violette decides to help the Buddies run away. Enter a spoiled rich boy named Bartleby who wants Air Bud as a birthday present, a dim-witted cousin, and a doltish thug employed by Bartleby's father, and mayhem prevails as Buddy and Molly get dog-napped!

Now, it's up to the Mane 6, Violette and the Buddies to rescue Buddy and Molly before they get captured themselves.

As the chase winds over the river, through the woods, to the drive-in movie theater, and straight through the farmyard, slapstick comedy and satire reign and the whole gang learns an important lesson about the value of teamwork, love, and courage.

(S3E11 of G5 Adventures)

Normally, Izzy Moonbow is a very cheerful and happy pony, but sometimes, things start to get just a bit too much for her to handle, which can quickly cause her to spiral if left unchecked.

Sunny Starscout has always been very patient and helpful for her, and now is no different once she starts noticing the signs that her unicorn friend is starting to struggle from all the sensory overload during a particularly hectic visit to town.

Content: An autistic pony on the brink of sensory overload and a friend who understands her there to help in her time of need
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This is partially based on my own experience, some things I happen to have seen on the topic, and also with the assumption that Izzy Moonbow is on the autism spectrum, which to be fair, there are certain 'patterns' she has that myself and many others on the spectrum pick up on. _{Or perhaps AuADHD, being both autistic and ADHD.}

This story is a sequel to G5 Adventures in Muppets from Space

After finding out the map they were given at the end of their last adventure will lead them to the Dragon Lands, the Mane 6 head there to let the dragons know that Opaline isn't a danger to them anymore. But while they are convincing the dragons they mean no harm, they are called on another Unity Quest... this time, it may be their biggest adventure yet.

When SpongeBob’s beloved pet snail Gary is snail-napped, a trail of clues lead him, Patrick, their sea-unicorn companions and the Mane 6 to the powerful King Poseidon, who is keeping Gary in the Lost City of Atlantic City. 

But… he’s not the only villain in this story that our heroes will have to deal with. Allura and her minion Twitch are here as well, looking for a fragment of a very powerful star that will lead Allura to other realms, and Sunny and her friends already have one of those pieces in their possession already. If she gets the rest of those pieces and combines them, she will be unstoppable.

On the mission to save Gary (and unknowingly, the entire ocean from Allura), the Mane 6 team up with Bikini Bottom friends, old and new, on a hilarious and heartwarming journey where they discover nothing is more powerful than family and true friendship.

(S3E3 of G5 Adventures)

This story is a sequel to Sonic The Hedgehog x My Little Pony: A New Generation - Revisited

Doctor Eggman uses the energy from the Unity Crystals that Sage extracted to build an empire by dragging several cities from other dimensions - including Equestria. Upon realizing this, Sonic and his friends manage to reach Sunny and hers, so they can all join forces once again to bring down the empire Eggman has raised.

This story is a sequel to G5 Adventures in LEGO DC: Shazam! Magic and Monsters

As the end of summer looms near, Queen Haven and Alphabittle have arranged for their wedding to take place in just a few months, but the only thing they can’t seem to agree on is if Alphabittle will leave Zephyr Heights to be with Queen Haven so they can rule together, letting tensions rise between the couple. But with the Mane 6 and Sparky playing important roles in the ceremony, they don’t want to step on any of their hooves. Luckily, the Unity Crystals call our heroes, Alphabittle and Queen Haven on another Unity Quest and a family vacation that might settle the tension.

Solving mysteries is the last thing on Mystery Incorporated’s minds when they reunite with their pony pals, Sparky, Alphabittle and Queen Haven when Fred's parents invite the group on a luxury cruise to celebrate Fred's birthday. But as it turns out, the cruise is actually a mystery cruise, but the gang solves all the Program Director's mysteries so fast that it looks like their trip to the Bermuda Triangle will be an uneventful one full of rest, relaxation, and all-you-can-eat buffets.

However, our group find spooks and scares on every corner, from alien sightings to terrifying ghost pirates that like to sink cruise ships with cannonballs. And things go from bad to worse when the ghost pirates kidnap Fred’s parents! And to make matters worse, if our Equestrian heroes and their friends, both new and old, can’t solve this swashbuckling mystery, they may have to end up walking the plank and become the Bermuda Triangle’s next victims!

Hold onto your cutie marks, your crew and your Scooby Snacks for a high seas adventure that you’ll just have to see to believe! 

(S4E18 of G5 Adventures)

(I have to thank CortezDude again for his amazing poster!)

This story is a sequel to G5 Adventures in Scooby-Doo! in Where's My Mummy?

After their most previous adventure in Egypt, the Mane 6 decide to take Allura and Twitch to visit Spike and the rest of the dragons on the Isle of Scaly, as well as warn the dragons that Alterro is looking for the legendary alicorn land of Skyros, and could come after the dragons as well. The dragons (except for Spike and a few others) are reluctant to prove that Allura’s changed, after all the things that the Mane 6 have said about her, but Allura and Twitch may get the chance to prove themselves as they are summoned on the Mane 6’s next Unity Quest adventure.

Upon arriving within the bustling city of Los Angeles, where humans and anthropomorphic animals co-exist, our heroes soon uncover who they are supposed to help-- a group of notorious villains known as the Bad Guys-- Mr. Wolf, Mr. Shark, Mr. Snake, Mr. Piranha and Ms. Tarantula, who are also the mentors to five Mythix Tiger cub cousins-- Reva, Carmine, Gretchen, Zari and Oran, all while under the watchful eye of a mysterious dragon named Safira, who has fire imbued with dark magic.

But then… one day, the Bad Guys and their young apprentices are finally caught in the act. To avoid a prison sentence, the animal outlaws must pull off their most challenging con yet: becoming model citizens. Under the tutelage of their mentor, Professor Marmalade, and with the help of the Mane 6, Allura and Twitch, the dubious gang sets out to fool the world that they're turning good.

Will the Bad Guys fool everyone, including our Equestrian heroes, or will the feeling of good cause them to really change their ways?  And what are Safira's true motives for the Mythix Tiger apprentices?

Based on the best-selling Scholastic book series, and packed full of heart, action, laughs and the true meaning of goodness and friendship, G5 Adventures in The Bad Guys proves that being bad has never been more fun.

(S4E3 of G5 Adventures)

This story is a sequel to G5 Adventures in The SpongeBob Movie: Sponge out of Water

The Maretime Bay Amphitheater has officially been built, so musicians have an official place to perform in Maretime Bay. But the good feelings don't last when the ponies are sent away on an important and musical mission.

Scooby-Doo and the Mystery Inc gang team up with the Mane 6, the one and only rock-and-roll band KISS and four princess bat pony sisters in an all-new, out-of-this-world adventure! The Mane 6 reunite with their friends at KISS World, the all-things KISS theme park, to investigate a series of strange hauntings. With the help of KISS and their royal bat pony friends, they discover that the Crimson Witch has returned to summon the Destroyer from the alternate dimension of Kissteria!

The ghastly duo's plan? To destroy the Earth and any other realm they come across... including Equestria!

Can the gang's cunning, the ponies' magic and KISS's power of rock save the day? Tune in to this rock-and-roll mystery for some thunderous, heavy metal fun!

(S1E6 of G5 Adventures)