Forbidden Siren is a horror survival game released on the PS2...and it definitely emphasizes survival. This has got to be one of the most difficult games I have ever played, and its limited popularity may be due partially to the difficulty. Players can literally spend hours on a single mission, mapping out various methods of getting around the enemies. And that's what ups the replay value of the game, the fact that there is no single way to beat the game.
The game follows chronological timeline; players get to navigate an island filled with its former inhabitants in...undeadish form with over 10 characters and unravel the mysteries surrounding the island. Now, because I never actually beat the game myself (or actually made it past the half-way mark), I couldn't really tell you about the story. From what I remember, the island is surrounded in this red liquid and the island is shrouded in darkness due to a misguided ritual. And also... the characters have some variety of an English accent. Actually, it made things pretty comical.
The gameplay alone makes it one worth attempting. Players will navigate through maps of undead people, most of the time armed with absolutely no weapon--and folks, there's no fisticuffs in this! There will either be a weapon provided through the course of the map, or the character will start with one. Many times, players will have to traverse the map with no weapon... while the enemy is fully armed with rifles and the like. The point of the game is strategy and avoidance tactics.
Forbidden Siren offers a unique feature called "sightjacking". You basically see the map through the eyes of the creatures. That is how players map their course, by keeping tabs on the enemy and using the environment to provide diversions. And these things aren't immediately noticeable. Other than the battle system, the rest of the actions are menu based (such as picking up items, or observing them). It's another level of difficulty, actually having to go around and figure out what you can use and what you can't. In fact, after the main session of missions, players are taken again through those same missions for seemingly out of the way and completely pointless tasks that will trigger different scenes and further develop the story. But mind you... they're often difficult to point out without a guide. Or I could just be plain awful at the game... which honestly wouldn't be a lie.
Forbidden Siren!