HAUNT

Recovered games by Denk
Any game which has been practically unavailable for a long time for most players but is now again available to play, though there might be differences from the original version.

IF that purposely conceals crucial player character information by Puddin Tame
IF that doesn't explicitly clue players in on knowledge they would/should have if they actually were the player character (The character's motivation, interests, relevant parts of their past etc.), which, for good or bad, results in some...

Games With Extended Underwater Sequences by Canalboy
That is games that have immersive (pun intended) sub aqua areas of more than, say ten locations.