Alternate Fantasy Dimension Generator

 This tool is for generating fantasy worlds somewhat like the one where your story takes place, with multiple fantasy species, diverse ecosystems, and dense with adventure locations. It might be useful if the PCs somehow travel to another dimension without a lot of time for you to prep. Some planes are traditionally ascribed to having a material theme (like fire, water, nightmares, etc.) or ethical valence (lawful evil, neutral stupid, rancid vibes). For those planes, I bet this generator still works, but you'll have to manually replace all the cities with fire cities and the presidents with fire presidents and so on.

The generator starts by describing inhabitants of the fantasy world in general. There will be a lot of variation, just as in your main fantasy world there are probably all sorts of strange creatures, but hopefully the prompt will give you a baseline to riff off of. It will then run through a survey of the intelligent humanoids, divided by broad regions which contain one or more culture groups. Even a single culture group should be imagined as containing diverse multitudes, both to awe with versimilitude and to give you leeway as you fill in any gaps over play. You could imagine the whole setting seen in Lord of the Rings as happening within one or two culture groups. Especially when culture groups in the same region are of different types, it's likely that there is great intermingling, and one spot might be home to all of them.

I hope you find the way I've simplified an entire fantasy world to be useful and intriguing, rather than a statement on good practices in anthropology.