Cloneland provides an exact copy of your current world in a whole new dimension. It requires a very expensive Cloneland Teleporter and it will instantly transport you to the other world with one click. This will slowly damage the item so be aware of its limits.
There’s something very helpful in having the ability to switch between two worlds instantly. In essence, you have twice the items available to you at any given time. If you’re ready to harvest your crops you can do so in the Overworld and then jump to the Cloneland for a second yield.
If you happen upon any ores, especially diamonds, then just mine those and head on over to Cloneland for double the items!
And if you’re in a sticky situation like you’ve turned a corner to a room full of angry mobs, just click the teleporter and be instantly removed from the situation.