Simple Void World is a mod that adds a single block that acts as a portal to a tiny world with a bevy of options to customize to your own liking. The world starts you out in a 7×7, single-layer block with another portal block to get you back.
From there, it’s up to the player to decide how to use this new world. You can keep it as your private storage realm or even house an ender chest there to keep your most valuable items away from prying eyes.
You could even set up an enchanting or crafting room to take that away from your main building area.
The block can be expanded exponentially and you could even build a second city here if you so choose.
There are a few limitations and risks involved so be aware that you can’t set up a bed or make this world a spawn point.
And obviously since it is a Void world you risk falling off into the great unknown.
And this mod requires an additional API to run found here.DownloadForumInstall Guide