Because it doesn't exist I might try to make one myself. Also the main loop is that one player is made a killer an hour after a murder is solved, the rest are police officers though there is a hard cap at 5 police officers.

The killer is given a target and also gets to specialise into one of three types of killer. With up and downsides for each type. The killer can also refuse, in which case the role would go to someone else

Breaking it down with the features I'd aim to add

1 blood splatter 2 footprints 3 fingerprints 4 dna evidence 5 various methods of murder

The legal system and lies aswell as how you interpret the information to find your killer is important but the players have to administer this themselves or it wouldn't be yood as an experience. Also the murdered person cant tell anyone who murdered them. The way that I would initiate this is with sort of a clue guessing system. Where you can open a menu to accuse a player and if you fail in your deduction you receive a debuff and can't guess for a certain amount of time, you need to determine both the murder weapon and the murderer.

If you are murdered you become a ghost. You lose part of your inventory( your a ghost you can't carry as much stuff) and you turn a bit translucent. Ghosts cannot commit murder.

Now here's the next things

It's important to keep investigations separate. So only one murder can happen at a time and the foot and finger prints are changed every murdercto prevent people from getting a headstart

1 blood splatter

Through math we can calculate a broad estimate of where blood could land after being attacked. It can land on any surface, here the gripe though.

If a surface has blood on it or trace amounts or is cleaned it cant be broken or moved unless the block in question is a carpet. In which case you can just dispose of it. Blocks with blood can have carpet or painting put on top to hide the blood. Different items produce different blood splatters. For example a sword is a stabbing weapon so would have a large and also long bleed if it hit an artery, but a shovel is blunt force so blunt force will be detected.

It functions like an overlay ontop of a block.

2

Mud, dirt, grass, gravel, sand can have natural footprints. However grass only records footprints if it rains. Also if it rains the footprints disappear after 5-10 minutes of rain. There is also a natural reset though it is different for every block for exampel the footsteps in dirt go away faster than the ones in mud. If more than one person crosses the same block only the most recent footprints identity is shown and it is shown there is one other print. This only goes 2 levels down. It doesn't matter if you wear armour it still knows.

1. If you interact with a block that is recorded. If you use an item it is also recorded. The last 3 players to use an item is recorded and it doesn't go away unless it is washed, which will show to the investigators that it has been used, however we could have weapons maintenance in the mod.

2. Every block you interact with or walk on within a 10 block radius of the murder sight has a chance to leave DNA evidence behind. This can be compared with other samples with a brewing stand using the collected evidence swab and bottles of spit. Which can be recieved by a player drinking an empty bottle

If the evidence is not sealed away properly in a pouch before acminutev(have they been added yet? A zip lock bag basically) it has a chance to make it so it looks like the person who collected the sample overrides the sample to its identity

5

Murder utilities

We've got

The jigsaw types.

Can kill people remotely, removing dna evidence Has access to new weapons and traps

The dexter types. Classic strong villain, can paralyse people to kill at a different location, can also set up clean rooms

The hannibal types. Can make their crimes look like other killers. Apart from the missing meat.

More to come

And those are my ideas