Looking for Mystery boardgame with specific mood

Well, since you mention Dangan Ronpa, why not read Umineko no Naku Koro ni. Wonderful and confusing mystery and really gets you thinking about it. Although make sure you get the new sprites from the ps3 version, the old ones look terrible.

Penumbra collection mate,very great ..
And for multiplayer get Infestation: Survivor Stories, Left 4 Dead 1 & 2 ,beasts of prey(don't get The Stomping Land it mega sucks..i wish i knew BoP comes out 2-3 days later pff :( XD ) , Rust, DayZ, 7 Days To Die , if you have great PCs get The Dead Linger too,etc.

Zombie Panic Source is free and very epic ,on Steam ( their new game ,storyline-wise too,is Contagion)

Arkham Horror, maybe.

This tabletop game is played on a board depicting Arkham City from H.P. Lovecraft books. Each player randomly receives an investigator they are going to play. Each investigator has their own background story, stats, starting items, home location and special skill. Together players have to prevent awakening of a powerful ancient monster in a certain number of turns - ancient monster is picked randomly from a set as well. If they fail that, they'll have to defeat it in combat. Players can move on the city map, fight or sneak by "common" monsters, collect magical items and clues, seal rifts to alien dimensions. It's not a competitive game, more like co-op.

This game is very complicated though. There are a lot of cards of different types, counters and markers. Players can adjust the stats of their investigators in the middle of the game, there are not only health meter to keep track of but also sanity meter, some cards provide additional "global" effect while they are in play etc.
I only played it once and we all died horribly in the end.

possibly Carnival Zombie? Or Betrayal at House on the Hill how about Mansions of Madness

all pretty good from my plays of them, carnival zombie and mansions of madness appealed to me the most, betrayal at house on the hill is probably the closest thing to what your looking for. but mansions of madness is probably the heaviest, not as heavy as Arkham Horror but pretty high up there.

come to think of it, also Witch of Salem was pretty good from my recollection.

never heard of the things you mentioned it should be like so im sorry if these don't fit.

I'm not sure if it's exactly what you're looking for, but you might consider Fury of Dracula.

Well it's not an exploration game, but I had many fun filled hours with Doom The Boardgame and it's expansion too. YES It IS the FPS Doom's Board Game adaptation, and with the expansion you can play classic Multiplayer modes like CTF, TDM, DM and other things :D Link: http://boardgamegeek.com/boardgame/10640/doom-the-boardgame

Betrayal at House on the Hill. I've never played it but from what I saw - this might be the game you're looking for. :)

Nightmare and Hero Quest.