Construct the infrastructure to rebuild civilization. Set up supply lines, mine skyscrapers for plastics, and find a place to process all the poop your people will generate. You have twenty minutes.
Farms generate food—those are the green dots you see below. All food is bright green. That's how you know it's fresh.
Build apartments. People will take in food and generate work. And they'll poop. But you don't have to worry about the poop right now.
Trails will convey resources like food and work between buildings. There's a limit to the volume of resources they can carry at any given time, so you'll need to plan your layout carefully.
Extend your reach by cutting through forest and... Uh oh...
So, you build a landfill to take care of the poop. Where was I? Cut through forest to get to ancient skyscrapers, which you'll mine for metals and plastics—you're an ace recycler!
Time to expand to other forests! But try not to tear them all down. Set up a water turbine and energy transmitters to power your search for more trees. And build some parks for points. Now you're cooking. Build a dozen high rises. More parks!
You just rebuilt an entire civilization in 20 minutes! That's no mean feat. Heck, it's going to take folks 30 minutes to do it in the sequel.