Ash's Adventures of An American Tail: Fievel Goes West is an upcoming Pokémon crossover made by Daniel Esposito. It will be uploaded on Google Drive as part of a double feature with its predecessor Ash's Adventures of An American Tail in the near future.
Several years after settling in to their new home in The Bronx, New York, the impoverished Mousekewitz family soon finds that conditions are not as ideal as they had hoped, as they find themselves still struggling against the attacks of mouse-hungry felines. Fievel spends his days thinking about the wild west dog-sheriff Wylie Burp, while his sister, Tanya, dreams of becoming a singer. Meanwhile, Tiger's girlfriend Miss Kitty leaves him to find a new life out West, remarking that perhaps she's looking for "a cat that's more like a dog."
Tired of chasing, Cat R. Waul devises a plan to deliver the mice into his clutches. Using a mouse-cowpoke marionette, he entices the neighborhood mice, including the Mousekewitzs into moving yet again to a better life out west ("Way Out West"). Tiger chases the train, trying to catch up with his friends, but is thrown off course by a pack of angry dogs. While on the west-bound train, Fievel wanders into the livestock car, where he overhears the cats revealing their plot to turn them into "mouse burgers." After being discovered, Fievel is thrown from the train by Cat R. Waul's hench-spider, T.R. Chula, landing the mouse in the middle of the desert. The Mousekewitzes are heartbroken once again over the loss of Fievel and arrive at Green River with heavy hearts.
Upon arrival at Green River, Chula blocks up the water tower, drying up the river. Cat R. Waul approaches the mice and proposes to build a new saloon together, although intending to trick the mice into doing the bulk of the work and then eat them afterwards. Meanwhile, Fievel is wandering aimlessly through the desert, as is Tiger, who has found his way out west as well, and the two pass each other. However, each one figures that the other is a mirage and they continue on their separate ways. Tiger is captured by mouse Indians and hailed as a god. Fievel is picked up by a hawk and dropped over the mouse Indian village when fireworks scare the bird, making his feathers pop out of his body and reunites with Tiger. Tiger chooses to stay in while Fievel catches a passing tumbleweed, which takes him to Green River. As soon as Fievel makes his arrival, he quickly reunites with his family. He is unable to convince the others of Cat R. Waul's plans to kill the mice. However, Cat R. Waul happens to hear Tanya, Fievel's older sister, singing while working and is enchanted by her voice ("Dreams to Dream").
He sends Tanya to Miss Kitty, who is now a saloon-girl cat, and she reveals that she came at the request of Cat R. Waul. Cat R. Waul tells Miss Kitty to put Tanya on stage. With a little encouragement from Miss Kitty, Tanya pulls off a great performance for the cats ("The Girl You Left Behind"). Meanwhile, Fievel is chased by Chula and briefly taken prisoner, but escapes.
While walking out of town, Fievel stops to talk with an old hound sleeping outside the jail, discovering that the saturnine dog is in fact the legendary Wylie Burp. Fievel convinces Wylie to help and to train Tiger as a lawman and as a dog. Tiger is reluctant at first, but relents at the suggestion that a new persona might win back Miss Kitty. The trio go back to Green River to fight the cats, who had scheduled to kill the mice at sunset. At Green River, a giant mousetrap has been disguised as bleachers for a ceremony honoring the opening of Cat R. Waul's saloon. But before the trap can be tripped, the three foil the plot using their wits and their slingshots. But towards the end Chula captures Ms. Kitty as hostage, threatening to drop her from the tower. Tiger snaps and saves Ms. Kitty and using a pitchfork and Chula's web as a lasso with him trapped on it to hurtle Cat R. Waul and his men out of town by having them piled on part of the mousetrap, which the heroes use as a catapult. The cats fly into the air, then land into a mailbag. The train picks the bag up and leaves.
Enchanted by his new personality, Miss Kitty and Tiger become reunited. Tanya becomes a famous singer and the water tower flows with 9000 gallons of water again, making Green River bloom with thousands of flowers. Fievel finds Wylie Burp away from the party who hands Fievel his sheriff badge. Fievel is unsure about taking it, since he feels he is not a traditional hero. However, Wylie reminds him that, if Fievel did not meet him, he would still be a washed up dog. Realizing that his journey is still not over, Fievel is told, "if you ride yonder, head up, eyes steady, heart open, I think one day you'll find that you're the hero you've been looking for".
- The Vultures (Buzzie, Flaps, Dizzy, and Ziggy), Jiminy Cricket, Zazu, Kronk, Zhane, Korra, Mako, Bolin, Asami Sato, Jeremy the Crow, the 100 Acre Wood Rebel Alliance (excluding Mewtwo and The Good Fairy), The Masters of Evil, and The Crime Empire guest star in this film.
- This film will be dedicated to the loving memory of Dom DeLuise (1933-2009), who voiced Jeremy the Crow in The Secret of NIMH 1 and 2 and Tiger in the real film and died of a kidney failure, and James Horner (1953-2015), who composed the real film's music score and songs and died in a plane crash.