Anyone alive still? Mapping Question, Count Down Mission Timer Options

[mg1999]

If anyone is still alive on here I was hoping I could get some guidance on how to create a count down mission timer. For example: A countdown timer displays 30 minutes at the start at the game, and at the end once it reaches zero, the game ends.

Would love to know the answer here as I am stumped looking for the correct trigger.

Thanks!

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