Investigation Games

Which RPG are there that really focus on the idea of mystery solving and detective work? I'm interested in running something along those lines but most I know have 'Eh, roll a skill I guess' as the limit of the mechanical stuff about detective work.

There's the GUMSHOE system, that focuses on investigation and the resources that the characters can bring into it.
The idea is that an investigation can't really fail, since the show must go on, but there can be setbacks and wasted resources.

I'd recommend looking at anything using the GUMSHOE engine. It makes it so that the players never roll to find out information, instead, they get the bare bones automatically, get more specific information simply by naming their action and having the appropriate skill and can gain extra details by spending resources. It makes the game about figuring out where to look and piecing together the information once you have it, instead of rolling to gather information until you solve it. It also makes it impossible to have a scene where the players have no idea where to go next by making sure there's always a bare minimum amount of information they can gain, it's not enough to solve anything, but it's enough to figure out where to start asking questions.

Any system can work as long as you build the mystery well. For one, don't roll the dice unless there's a possibility of failure. If your players know the cabinet has a secret drawer, they don't have to roll to find it. If they suspect it does and say "we pull on the wood between the drawers," don't roll for it either. Or if they find out the murderer was a smoker, "I search for cigarette butts" should now just be successful if there are cigarette butts. Encourage logic over dice rolls. Dice rolls are for uncertain outcomes, like searching the room for something.

Also, never have a single vital clue. Always have multiple clues leading to the same conclusion, and then multiple clues leading to those clues. That way if the dice say they miss the clue, they can still double back and follow up on one of their other leads.

To be precise: detecting clues can't fail. The players can fail to assemble the pieces, however.

If GUMSHOE, then I recommend in particular Mutant City Blue. Superpowered cops hunting superpowered criminals.

But even Call of Cthulhu works very well - for investigations within a more conventional system.

That sounds more like it's trying to simulate a mystery procedural than having the players solve a mystery. There's a lot less challenge if you can't miss vital pieces and have to figure things out with imperfect information.

You missed the boat on Invisible Sun, although I'm sure the grand mystery they were promising is going to end up fucking laughable. I can't watch teardown videos of the box on youtube and see all those precious fragments of knowledge end up on a wiki.

Any system will work. Literally any system as long as it has a search skill, and a few social skills somewhere in it.
Finding clues is all you need because the player will need to use their brains to figure out the solutions to a logic puzzle. If you allow them to roll a skill in order to do the actual logic, then they're not challenged. They just built their character correctly.

you can't miss a few really basic clues, the vast majority of information can be missed

But why even bother if your PCs can't fail? If they always have the information they need to win, then there's no stakes behind the investigation. There needs to be a point where the trail can potentially go cold if they're not good enough at their jobs.

as I've said already: they don't
they have some very basic facts as a starting point, not enough to solve the mystery, they can still miss other facts and come to the wrong conclusion as a result

So if you can't fail to detect a clue, then isn't the only challenge figuring out what location to go to next?

you have to think of where and how to look for clues, I've run the system, believe me, players miss more clues this way than you'd think

Yes but I was looking into systems that mechanically support it.

mostly but you also need to declare the right investigative skill in the right location. while you could simply go through your skill list, any GM with self-respect would clamp down on this tactic.

Also putting the clues together to get an end result.

>as long as you build the mystery well
That's my question exactly. How do I into this?

Work backwards. First, come up with the solution. Whodunnit, Whydunnit, Howdunnit. Then come up with a piece of smoking gun evidence for each of these. Then hide them somewhere almost impossible to find. Then come up with at least one piece of evidence that strongly hints at each of these conclusions, as well as how to find one of the smoking guns. Note that it doesn't have to be the same smoking gun; a clue that hints to whodunnit can also hint to whydunnit's smoking gun. Then hide them somewhere a little bit easier to find. Then repeat this process at least once but as many times as you feel comfortable with - each clue should point towards a conclusion though more vaguely than the tier above it, and should point towards at least one higher-tier clue. Then, take all your lowest tier clues, and either put them in a single scene, or put something that will directly lead to all of them in a single scene.

Now your players have multiple clues to follow up on, and each leads to another. But that also means they can overlook a clue, alienate a clue-holder, let a clue be destroyed, and so on, and they'll have more leads to follow.

But pay attention to those leads they've missed. If they've fouled up all possible connections to the smoking guns, then the mystery is over. Give them one last chance to make a miracle happen, then let them know the trail has gone cold, and in the end, they never caught the killer. And end the adventure. Do not have the villain confront them, do not have someone drop a clue in their lap. The greatest freedom in a game is the freedom to fail, and if you rescue them when they're failing then the whole exercise is pointless.

what about an urban fantasy/paranormal setting?
I just need a simple system, not too crunchy, and not too detailed. Where you can play as a Blue collar warlock-detective. Kinda like a mix of Hellblazer and ghostbusters.

Sounds like sensible advice. Thank you.

I've never seen The Great Mouse Detective, and I'm not sure that I want to.

Just use GUMSHOE or World of Darkness. Then slap on whatever fantastical creatures you want.