This is a paid asset, but now you can download Dark Fantasy Free.
Detail this asset from Unity Store: Original Link
Dark Fantasy
Create the twisted realms and dark kingdoms that have haunted our imaginations for a millennium. Use this kit’s shadowy castles, grim spires, chiseled gargoyles, magnificent edifices, plethora of doors, mysterious fountains and so much more to build the environments for your dragons, witches, knights, and other magical fantasies to spring to life!
Designed by Sebastian Luca, modeled by Jakub Vondra, and texturing by Alexey HrDesign, with cover art by Danar Worya.
Please note: Dark Fantasy Proceed with creativity! You are about to purchase a 3D asset kit that includes elements to set the scene as you build your world, whether it’s for video games, film, television, design, or art. These completely customizable assets will serve as the building blocks to help you create an original environment with Unreal, Unity, Houdini, Blender, Maya, Cinema 4D, and 3ds Max native file support. With a license you can download this kit in multiple file formats, all you need to do is create a free account. Inside this kit you will find: