A free app for Windows, by SPY Interactive.

In this app, you will have the chance to download and install several different kinds of assets, such as weapons, armor, tools, and many more. These assets are divided into categories, and they are sorted into the categories based on how similar they are. For example, there is a category of weapons, and they are sorted into it based on how much damage they inflict. The assets that you find in this app will allow you to construct your own worlds. This is not only an application for downloading assets, but it also gives you the ability to create and share your own worlds.

If you want to know more about this app, you can visit the website.