Ok guys this is a spoiler but remember in Crysis 2 you walked into Haregrove's mansion? Well i can't spell his name i know who cares lol. Anyhow you remember seeing 3 NANO SUITS in one room?
I have a theory. They died from the suit. They were dead walking man and prophet was the last survivor.
If you realized, there are EXACTLY 3 nanosuits in that room but i just remember Prophet vaporized at least 2 nano suit users. So that leaves Nomad and Psycho.
I bet they didn't make it or maybe they have another mission elsewhere not knowing what's going on?
I hope Crytek will consider a expansion story
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At first I though this could be a valid answer, but after a while I recalled that in the same room there is a massive suit (like double the size of the rest) with no helmet. That, I think, defeated your theory and the suits might just be some decorations.
Also the suits were slightly different. I assumed they were prototypes and previous iterations.
To OP:
No wide open areas? Have you even played the whole game? What about the defense of Grand Central Station, or the Cell bunker? Each of those is almost a square mile unto itself. Granted they're not as "big" as miles of repetitive forests, but that's because it's nowhere near as hard to litter the ground with trees and foliage as it is to faithfully recreate a New York cityscape.
Also, the story is very connected to Crysis 1, but you're right it doesn't deal with the aftermath, it picks up 3 years later. We have to assume everyone got off the island just fine though as the last we saw of Nomad and Psycho they were on a VTOL heading back to save Prophet who was lost on the island. Since Prophet is in New York, they clearly succeeded. But in my opinion their stories are not involved with with this one so there was no reason to try to connect them. Think about it:
In the flashbacks in Crysis 2 it became clear that Prophet was working for Hargreave independently of his role as Sergeant of Raptor team. Since he's right there at ground zero in Crysis 2 before the Marines are deployed and Gould and Hargreave both know he's there, we have to assume he left his military position. Meanwhile the events of Crysis 1 HAVE to have stirred up SOME military conflict with North Korea. I mean they were smuggling WMDs and kidnapping researchers and we responded by killing hundreds of them. It's natural to assume that Nomad and Psycho just got reassigned in that conflict. Remember that at the beginning of Crysis 2, no one but Hargreave and Prophet know the Ceph are invading. It starts out as just a virus and unfolds very quickly from there. They probably just didn't have time to recall Raptor Team.