(Image credit: Unknown Worlds) What if survival weren't optional? That is both a useful way to explain why you can respawn in a videogame, and one of two central questions in Subnautica 2 . The other is: Would morphing into some weird alien thing really be so bad? The highly-anticipated survival game is out in early access today, and after a handful of hours, I think it's a lot of fun. Like the original, Subnautica 2 is mainly about exploring an alien ocean, seeing cool, weird alien fish, getting eaten by cool, weird alien monsters, and building a cool (but not really weird) underwater base. Thumbs up to all of that so far: Subnautica 2 is refined for an early access survival game, more than a lot of 1.0s. (And it has co-op this time.) (Image credit: Unknown Worlds) But there might be hope for something different.…