Project Tomorrow Rebuild a dead Earth, defend it

You start with almost nothing on a planet that wants you dead. Explore to gather materials and find hidden caches of food, water and seeds, then put them to work: grow crops, build water purification, keep the colony fed. Resources are limited, so every crate you spend on one thing is a crate you didn't spend on another. It's classic survival crafting with a sci-fi coat: hands in the dirt first, luxury later. The stakes stay real because the world doesn't hand anything back once it's gone.

Your base is the whole plan. You lay it out, expand it, and decide what earns power, walls and upgrades first: living space for the colony, machines that push the terraforming forward, or defenses for the night something big comes. The terraforming machines are both the goal and the target, so where you put them matters. Sandbox building means there's no single right layout, only the one you can defend. As a colony grows, so does the list of things that can go wrong with it.

Fixing the planet is loud work. As alien hostility grows, waves come to dismantle your machines and base, and repelling them means building defensive structures and upgrading your arsenal between assaults. The tension builds wave by wave until something breaks, and what breaks is usually the part you underfunded. Difficult, casual, or somewhere between: modifiers let you tune the pressure.