Make the Pacific way to get the achievement.
Save the game after the last quest,on Friday, before going home, finish without killing anyone and you'll get the following achievement:
The Anustart! achievement in POSTAL 2 worth 32 pointsCompleted the "POSTAL 2" game mode with no kills.After, load the last save and start killing everyone with the shovel (at this point I assume you have at least 5 "health" pipe)