Not much as a "playable" game however it does simulate on a "Google Maps" scale of what would happen during a zombie outbreak. You can customize amount of living, and living undead, and also include how accurate civs are with weapons, how many cops, etc etc.

Truly an amusing time-waster.

Protect thousands of civilians over a 1km square area in Washington DC, north of the White House and Pentagon, and adjacent to the Catholic University of America. Keep an eye out for infected civilians, and make sure none find their way outside of your police unit's reach.

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