Twelve characters isn’t an opening chapter—it’s a party! And it’s overwhelming. No reader can keep that many new characters straight, especially when two thirds of them are just names. That’s a clear sign you’ve fallen victim to backstory, where you explain your protagonist’s life or describe her predicament in full. Don’t do that. Chapter One should focus on the protagonist, revealing her main concern and hinting at the journey or challenges ahead of her. You may do this with the help of a secondary character or two, but keep the number small, and have them acting upon or reacting to the protagonist, keeping the spotlight on her. There’s no official number of characters for the first chapter, but ‘fewer is better’ is a good rule of thumb. Next time, instead of writing a big ol’ party, imagine your readers at a big ol’ party. They wouldn’t get some voice-over delivering the history of every party-goer as they walk in the door. They’d meet a few of them, one or two at a time, one question-and-response at a time. At the end of the night, they’d go home with a solid feeling for two or maybe three people. Perfect. There’ll be plenty of parties for the folks they didn’t meet tonight—just as there are plenty of chapters in your book for the characters in the wings.