Synopsis:
Twenty years have passed since the kingdom was overthrown by Emperor Mordecai. Hand-selected in their childhood by the madman himself, Jareth, Brinna, Kellan, Anni, and Rowan come together with a myriad of others, uniting races and classes in an attempt to overthrow the tyrant...

Now adults meeting for the first time, they must overcome their differences and learn to work together, but it won't be easy, as they come from diverse backgrounds. It will take all of them together to stand a chance of uniting the people against the Emperor, who inspires fear into the hearts of men.

First off, titles are hard. They're often chosen by the publisher in the last stages of editing. For a fantasy novel, it's typical to have a title referring to the setting or the main theme. If you choose setting, your title would be based around whatever name you've chosen for your fantasy world, i.e. "Medallon", "Knights of Avalon". This option is good if you plan to have multiple novels taking place in the same world, or if the world itself is unique, interesting, or crucial to the story.
The other option for a title would be the novel's main theme. It should be purposely vague enough to not give anything away but also interesting enough to set it apart from other novels. For your story, a good title in this category might be "Emperor's Bane".

You mentioned overcoming differences a couple times, if it is a big part of the story, i would have that as an idea
Split Unity, Handpicked Unity, stuff like that.

You'll wanna keep it short and sweet. That's the main thing.
Pick out a main idea, or a word that represents the story as a whole as well as possible.
Make it memorable.

(Also note that it has to be mostly original.)

My working title is Children of Fate's Hand, because Fate ends up playing a role in the story. There are 12 deities who are all siblings, then there's Fate, who's the oldest of them all and isn't included in the pantheon of worship because she's viewed more as a force that keeps the other gods in line.
Other ideas have included: Born of Fate's Gambit, Chosen by Fate, The Emperor's Gift, Fate's Betrayal, Two Sides of A Coin, and Born Twice Royal.

The main theme revolves around sacrifice and the fact that even if good wins, it comes with a heavy cost that might be too much to pay. The heroes have to figure out not only how to work together when they all come from different backgrounds, but how much are they willing to lose? And how much are they willing to make other people lose... It's easy to make a choice that only affects you, but when other people get hurt because of it, that choice gets harder.
They also come to learn that even those who seem to be the most evil, do have a shred of humanity and have been broken themselves. It's grows harder to hate someone when you understand their pain...

The Random Teen who Drank Too much Vodka and Wants to FUCK his Reflection

I don't even have any teens in the story, and it's not a YA novel, so no.

What's YA?

That's Spidey's current mood.
For a title, Fate's Gamble or Fate's Debt??

Young Adult

It's not much of debt, really. She's just trying to nudge people to put the world back in order. She influences, very much behind the scenes, but never interferes directly, as some of the other gods occasionally do.

Considering the titles you’ve provided, think about the audience of the story. What kind of title would they be attracted to? I like the Emperor one