!!! STALKER GAME SPOILERS !!!
Strelok (Ukrainian) – S.T.A.L.K.E.R.: Shadow of Chernobyl
Main character (player) in the game Shadow of Chernobyl, main antagonist in Clear Sky, present also in Call of Pripyat. In first part of S.T.A.L.K.E.R. series he has an amnesia and the whole game is focused on main quest that appears on PDA he has (even though he doesn’t know it is not his) – “Kill Strelok”. In second part of series – Clear Sky – that is prequel to Shadow of Chernobyl, he tries to get into power plant and must be stopped. In last part – Call of Pripyat – he is helping the main character. If remains alive, he will get a job as a chief in newly created Scientific Institute that is focused on the Zone researches.
Major Degtyarev (Ukrainian) – S.T.A.L.K.E.R.: Call of Pripyat
Main character (player) in the game Call of Pripyat. Agent of Security Service of Ukraine (Sluzhba Bezpeky Ukrainy), who is sent to the Zone to investigate a catastrophy and has to work in cognito. After completing his mission he gets advance to the rank of Colonel.
In fact 99% of characters in the series are Slavic, probably all Ukrainians. 99% because there is an easter egg, and corpse of Gordon Freeman.