"Comes with double sealed titanium doors and its own oxygen purifying system. Build a few of these, and when the apocalypse happens, you'll know where the crazy people are living so you can contain them"
The Underground Bunker is a premium building introduced in the 3.2 Patch that provides players with 4 more workers. It yields a very high amount of and and is comparable to a better version of the Suburban House. This is outweighed by the fact that this building costs a considerable 120 and that it takes 20 hours to collect.