In a fanfiction, the aliens could capture Naruto and try to study his unique abilities. The monsters then decide to rescue him because they realize his powers could be the key to defeating the aliens once and for all. The story could involve a lot of action as the monsters infiltrate the alien base to save Naruto.
One idea could be a story where the monsters and aliens have to team up against an even greater threat from another dimension. Maybe a powerful interdimensional being that wants to conquer both Earth and the alien planets.
The Missing Link is also quite popular. His brash and confident personality can add a lot of humor and action to a fanfic. He could be on a quest for glory or trying to prove himself to the other monsters.
Naruto's ability to sense danger and his strong willpower could also play important roles. In the Monsters vs Aliens world, there are often unexpected threats. Naruto's danger - sensing ability would help the team anticipate attacks. And his willpower could inspire the monsters when they are facing difficult situations. His ninjutsu skills in general could be combined with the unique features of the monsters, like using the Invisibility of the Invisible Girl and adding his own hidden mist jutsu to create an even more effective stealth attack.
There are many movies about humans and aliens (or monsters) fighting. The following are some classic works:
1 Star Wars: A series of sci-fi films directed by George Lucas about wars between planets and conflicts between different races, many of which involve aliens and extraterrestrial creatures.
Alien series: A series of sci-fi horror films directed by Ridley Scott that tells the story of human survival under the attack of alien creatures. There are also many scenes involving aliens and alien creatures.
"Blade Runner 2049": A sci-fi film directed by Dennis Villeneuve, which tells the story of a bounty hunter in the future searching for clones. It also involves the battle between humans and extraterrestrial creatures.
4. The Matrix series: A series of sci-fi films directed by Lily and Lana Wachowski about hackers and their resistance in a virtual reality world. There are also many battle scenes involving aliens and extraterrestrial creatures.
5. Thanos series: A series of superhero movies directed by Marvel Pictures tells the story of Thanos destroying all life in the universe through the Infinite Gloves. There are also many battle scenes involving aliens and extraterrestrial creatures.
The above are just a few of them. There are many other wonderful movies about humans and aliens (or monsters) fighting. You can choose according to your preferences.
The RWBY manga doesn't manage to fix everything that was off in the show. It does make some efforts, but it's not a comprehensive solution to all the show's shortcomings.
Well, I don't actually know the specific 'the day everything went wrong story'. But generally, it could be about a day when a person woke up late, missed the bus, then got to work or school and found out they had forgotten an important assignment. Maybe they spilled coffee on their clothes during lunch and later got into an argument with a friend. It's all about a series of misfortunes that happened in one day.