I've beaten the game, but when I go into my file the only options are Campaign, Missions, and options. How do I play raid mode?

Added after 9 minutes:

Someone please tell me

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"Squatted down and did a little dance, shook a little turd out of the bottom of my pants."

After finishing (I think) chapter 3 the first 7 RAID levels were unlocked for me. Have you actually 'cashed' your mission objectives yet? Go into missions and click the ones with an exclamation mark on them ('!').

Look up Missions, find the one that unlocks Raid Mode, and activate it.

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You can recylce a book and turn it into a paper plate, But it always is and will be, a book.

Thank you I feel like an idiot. I think that is a stupid way to do it, having to cash the missions.

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"Squatted down and did a little dance, shook a little turd out of the bottom of my pants."

I actually like it especially if you are receiving items such as extra clips of a weapon and you want to save it for use later.