When planning your next adventure in Dungeons & Dragons, there are a lot of movies, books, and mythologies... that could provide you with inspiration as the Dungeon Master.

Here are some ideas

Harry Potter

Eragon

Star Wars

The Owl House

This cartoon show is actually really cool. Inspired by Bosch aesthetics, this is a very rich world with compelling characters and interesting details. I'm sure you can get inspiration for a Magic School, a magician's storyline, and a history of redemption, even sprinkle some romance.
The owl lady and her raven sister are great NPC inspiration. And an exemplary study on the lycanthropic curse, with a twist on the Owl theme.
The Demons' King is a cute but funny and violent inspiration for any familiar. Contrast his sweetness with fervor and passion. His delusions of grandeur, and his Napoleon complex contrast with his status as a pet, so you can mimic that contrast for a great ironic effect. He's hilarious.

Fullmetal Alchemist

Helluva Boss

The Lord of The Rings

Any list of inspiration would be fatherless without the great Tolkien.

Frankenstein

You may think it's an old tale that you already know, but trust me. Worth a reading.

Lovecraft

Racist as they get, and scared of absolutely everyone different. But being so full of phobias works well for scary stories.

Vox Machina

And many other Critical Role media. It is especially good for Game Masters.

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