Can i make a first person shooter MMO with unity?

I'd like to make an open world game were people can do anything. Multiple difernt story lines, jobs, missions, ect. I don't have unity or have ever used it. I'm just checking it out right now.

You can make whatever you want with Unity. Given unlimited time, naturally. What you're describing there has thousands of hours of work in it. But don't let me discourage you! You really can make anything with Unity, you just might have to aim a little lower to begin with.

You should check out the other questions on this topic. While you specifically ask for a First-Person MMO, the answers given on the existing questions should help you with your decision.

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