Stalker: Call of Pripyat → Quests → Hunt 2 (Unknown Mutants)
Stalkers have discovered unknown mutants in the tunnels beneath Jupiter. They need to eliminate the threat. The unknown mutants turn out to be a pair of Burers. Trying to shoot them down could result in death, and it's difficult. However, the knife proves to be a valuable asset – it prevents the Burer from using its abilities, forcing it to parry attacks, while the Burer itself only needs a couple of hits. The grenade launcher proves equally effective on higher difficulty levels.
As a reward, Zveroboy will give out 5,000 rubles collected by stalkers.
Source: gamer.ru
See also:
Space Pistol. Terraria and Meteorite