Here's a story idea I've been having, but I'm not sure if it's any good:

It takes place in an alternative universe (obviously), and it stars this young colt, maybe around ages 17-18, and he lives a pretty average life as a steampunk inventor and journalist. He wakes up one day and discovers that Equestria is starting to fall apart and a new organization, the Institution of Rebirth, is taking over. He doesn't know what's going on or who this group is, but doesn't want to stay and find out. He gathers as many gadgets as he can and tries to escape. He's attacked by some of the org. enemies and views as his friends are being kidnapped right in front of him. He escapes and becomes even more scared and confused and only prays that Celestia will fix everything.

A little while later he runs into a familiar white mare, Rarity. They bump into each other while fighting off enemies and trying to stay alive. Rarity describes to the colt that she's part of the Elements of Harmony and were tasked by the princess to take down this new organization. However, they were outnumbered and were captured as a result. They began torturing them in the most brutal ways and even did a number on Twilight. She explains how she was the only member able to escape their prison and was told to get help from the princess before anyone could find her and throw her back in her cell.

They decide to team up and look for Celestia together. They go from different places in Alt. Equestria to find answers and take down different members of the institution. While Rarity is trying to get help from Celestia, the young colt just wants to know what will happen to his home and to his friends, and their problems get worse when they see that even Celestia herself is trying to fight off this new enemy. They meet other characters along the way like Zecora, the CMC, Trixie, Lyra and other characters who they think could help.

This is all i got so far. What do you think? Does the plot need work? Any ideas for a title?

It sounds to me like a very OC-centric fic, which is something you should be careful of in an AU. I've found that one of the biggest draws when throwing people into a world that they might not quite grasp yet (like a lot of AUs are) is that you need to give them something to ground themselves on or relate with, or you might end up losing them. A familiar character or place is a good way, but with an OC main character that becomes more difficult.

So let's say the story starts out, your main character is introduced. Do you have something in mind to make the reader care for this character? Is it enough that they'll keep reading even if they don't quite grasp what's going on in the universe just yet? And as for the alternative-universe aspect of things, are you prepared to explain the details of what makes the world different from the norm in a smooth way over time so that readers aren't lost?

If you have yes to both those questions, just run with it and see what happens. Because at that point, my best advice is to move forwards writing the fic that YOU would want to read, and I guarantee there will be others who will have no trouble reading it as well, just as it stands. Beyond that, remember that everything you change away from what you'd most like to do, could make writing the fic more of a chore and less of an adventure.

Awaiting further advice from people in three.....two....

3878561 It most definitely has potential. Then again, I just finished reading an awful Alicorn OC fic, so everything has potential right now.

O'm sorry, but I'm got good with titles. I say "Go for it!" with the fic itself, though.

3878586 Well, i do have a few ideas to make it AU. For one thing, it'll take place in a steampunk universe since the main character likes to invent things for everyday use despite his age. Even though most ponies tell him to give up and that he'll never be a successful inventor, so that could add some sadness to his character in a way.

There will also be airships, tanks, firearms, steampunk clothes etc. in this universe. Another thing is when the attack does happen it will spread through almost all of Equestria and will cause an ultimate catastrophe. Usually with most fics I read that involve huge battles, invasions, and fights that aren't crossovers, they usually have the AU. tag on it.

That and some canon characters may or may not get axed off in this fic, and if a fic has that happen in the regular MLP universe it can tick off some readers. Or so I've been told. Anyway, those are just some ideas.

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Sadness isn't always the best option as a character hook, bear in mind. Perhaps flip things around and work from there: a main character that is reluctant to pursue inventing, but encouraged by others... and ends up having to pursue it for sake of the world, and in memory of those they've lost.

Just a possible alternate version. It's hard for sadness to be a character hook if the reader isn't already invested in the character.

3878668 So have him surrounded by ponies who want him to succeed and when they do pass, have him purse his dream for those who have encouraged him? Ok, i think i see. What about the other ideas?

I'll be honest, this doesn't sound very good. An OC main character, added steam punk for no real reason, and the EoH are exactly the same but were defeated offscreen before the fic starts despite the OC hero being able to defeat them with no training and improvised tools. So you have a nerd power fantasy male character who has to go and rescue the damsels in distress in a setting normally dominated by independant, well rounded female characters. That's the kind of writing decisions that leads to #JauneArcMustDie and other fan rage.