How did they manage to build such a huge base? (DOOM 3)

Have you ever been normal in factories? Today there are things that are cooler than the Martian complex in terms of size. And in the game everything is in the planet itself - in fact, they dug holes, trimmed them - that's the base ready.
Teraforming a planet is an extremely long process, it’s good if it works out in five hundred years. And then it will cost such a cost of materials and man-hours that even for the UAC from DooM 3 it still has to develop and develop.

Apokalipsis113
is in factories on earth. where there are suitable conditions, and not 200 million km, where there is no atmosphere, no roads, no resources really, a terrible climate, where there is nothing at all ... they have done too much crap)

Fan_Tiesto
They have interplanetary flights there quite a common occurrence. Moreover, due to the fact that they can shove matter in the voids of matter, the conditions of Mars are not a problem for UAC.

Fan_Tiesto
In the game, humanity, in fact, has just got used to Mars. No large-scale settlements, no wide infrastructure, no permanent residents - only business travelers. It is understandable - the human body is stupidly unadapted to Martian conditions. What's the use if they made the atmosphere breathable? No one would have canceled solar radiation and severe frosts, so they would still live there as at polar stations. What kind of terraforming is there when it is more profitable to improve the stations themselves.

Fan_Tiesto
In fact, "you could breathe" is just the smallest problem. In general, the game has a lot of conventions. For example, it is not clear how it was possible to increase the density of the atmosphere so that one can walk there without a spacesuit. It seems incredible. Also, the solar wind has not been canceled, as has the attraction of asteroids. There is no ozone layer.
Any more questions?

Fan_Tiesto
Mars did not terraform so that at least you could breathe?
Too difficult, there is no point in doing this. Maybe in a thousand years it will be easy to do, but not in the 23rd century =]