Is it like the original Descent where you pick out one big mission that's completely independant from the other missions. It might take a couple of hours to play and when it was done it was done or is it more of a campaign structure similar to Descent 2nd edition and Imperial Assault?

Is it like the original Descent where you pick out one big mission that's completely independant from the other missions. It might take a couple of hours to play and when it was done it was done or is it more of a campaign structure similar to Descent 2nd edition and Imperial Assault?

In the core game there are two "Operations" composed of six missions each with loose storylines. About a paragraph intro, then a paragraph of win text and another of lose text.

If either the UAC or the invaders win four missions, they win the operation.

There is no real progression between missions, though. Marines start fresh every time.