Mojang / Minecraft API.
Mojang API is a free Games & Comics API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Monster Hunter World data
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Trivia Questions
Yes. The Mojang API is listed in the Games & Comics category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Mojang API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the Mojang API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Mojang API is served over HTTPS, so it's safe to use in production.