The Bunker

With no one left alive outside, the level of radiation kills a person in a matter of minutes. But the bunker is intact and holds enough air, food, water, and fuel supplies to last an entire year. It is hoped that during this time, radiation levels on the surface will decrease to allow people out of the bunker. Problem is, no one knows what is going on in other parts of the Earth.

And then you see that things aren't so great in your bunker either as everyone got hit by a severe lack of oxygen. Apparently, the air-supply system in the bomb shelter was meant for fewer people than ended up in it! Now you have to sacrifice someone, or else you all suffocate and die in agony... Only those most important for building a new civilization get to stay in the bunker. You don't have much time to decide. Very soon the oxygen supply will run out, causing the players to suffocate.