I don’t remember exactly the number of hours, but I’d say less than 5! It’s tied to player level/story progression. You get your first one a couple of story beats after your first mission with a cutscene in it ( the data collection one)

Exoprimal has been my surprise of the year. Really thought it was mediocre after a couple hours in but then it opened up with more game modes, dinos and became way more team focused and fun. The 10 player raids are some of the most fun coop I’ve had in the last years