kind of? I mean, you can theoretically play all the story missions on your own. But you will still need to be connected.
The multi player aspect are when you team up with 2 other players and do a mission together. Raids and such require a few more players to do it effectively.
Its kind of a half open world. You are in an open area with a random selection of other players. Random encounters and guided mini mission/events occur there where you work alongside other players.
