In my game the player travels to a parallel dimension and their time machine gets heavily damaged. So now they have to use the resources in the world to rebuild/repair it. We can assume that the player can easily mine for stone and ores as well as build the necessary tools like pickaxes and smelters.
For example: Crafting a battery to power it would require copper, iron and clay (in reference to the Baghdad battery). The player can mine for these, use a smelter to refine them and craft using a workbench.
So what could be the roadmap to rebuilding a the time machine?
Plus: You can cheat by using magic if you'd like to get creative ;)