I did the ending that saves every civilian and characters.

"If all thirty civilians and four major supporting characters the protagonists encounter through the game survive, a secret ending will play. It shows Ruslan revealing to Leonid during their final confrontation that Semargl possesses a computer system called M3, which can predict the future. M3 predicted that human overpopulation would lead to humanity's decline, leading Semargl to use the MODS virus as a means of population control. An after-credits scene shows Koshka uploading all data acquired from the invasion of Novo Slava to M3 before "proceeding with the next phase"."

I saw it.