Tips for running Marathon (1994) as efficiently as possible:
“Don’t run background tasks while playing Marathon. This means you should quit open applications before launching Marathon and close open control panels in the finder. Also, make sure your computer isn’t printing.”
via - https://cdn.akamai.steamstatic.com/steam/apps/2398450/manuals/Marathon_Manual.pdf?t=1715354860
Hilarious because I still close every app before launching a game. Some habits never die.