Yes it should affect any game not paused..., but be careful there are many adverse affects not just in the game that could occur. Your actual computer system files will be changed, modified and you might see some....patchy results. If you do it wrong in the game you risk badly messing up some of the games timers, especially when you try to set it back while playing so that your computer shows the real time...
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Village Monk
"There's no place like 127.0.0.1"