One case could be a 'lost in a magical forest' case. You can create a story about a character who wanders into a forest filled with talking animals and strange, glowing plants. Another case is a 'time - travel mishap' case. For example, a person accidentally travels back in time and has to figure out how to get back while not changing history too much. And a 'discovery of a hidden world' case is also great. You can tell a story about someone finding a world beneath the ocean or behind a secret door that has its own rules and inhabitants.
Well, a case like 'alien encounter' is popular for making up stories. You can have a story where an ordinary person meets an alien and has to communicate with it, maybe to save the Earth or just to understand a different culture. Then there's the 'inheritance mystery' case. This involves a character inheriting something strange or mysterious, like a locked box with no key, and they have to figure out what's inside and why it was left to them. Also, the 'enchanted object' case works well. For instance, a magic mirror that shows the future or a cursed ring that brings bad luck to whoever wears it.
The 'orphan with a special power' case can be used in making up stories. Imagine an orphan who discovers they have the power to control the weather. They then face the challenges of hiding their power while also trying to find out where they came from. A 'parallel universe' case is also interesting. A character could accidentally cross into a parallel universe where everything is different, like people have different laws of physics or different social structures. And the 'rescue mission' case is a classic. You can make up a story where a group has to rescue someone from a dangerous place, like a haunted castle or a villain's lair.