SDE is an authentic story modification that presents a part of the alternative universe of the Half-Life world and tells the tale of a conflict between the rebels, the Combine, and a third party, for whom you have to play.
Depends on the quality and the specific model. And depends on free time, of course. For example, this model can be made in a couple of hours. But it took a couple of days.
Wow, lovin' these new variants!
How long did it take to create all these new vehicle models?
Depends on the quality and the specific model. And depends on free time, of course. For example, this model can be made in a couple of hours. But it took a couple of days.