Mineforgian
In this journey, you stand in one room mining cobblestone for a long... LONG time. Using new tools and villagers, you can collect quadrillions of cobblestone, and possibly beat it.
However I don't even know if its POSSIBLE!
This is an idea inspired from games like cookie clicker and Minevolution
Original map: https://www.curseforge.com/minecraft/worlds/minevolution
[Requires Optifine]
There are optional easy [maybe possible] modes for download!