The game's size is TBD. It is for up to N players, played over H virtual hours, with O objects.
Have H little boards, each tall and thin, able to accommodate N cards ranged vertically. To the right of each, space for some player/object pairs of tokens.
Also, a similar "dawn" board representing the N locations and which player starts in each.
For each of the N characters, H tokens representing that player. For each of the O objects, H tokens representing that object.
N character reference cards.
A deck of event cards.
Objective
The objective is to be the sole survivor at the end of a day of murders. But all the players are time travellers and can edit any point in their timelines by adding cards.
Characters
At the start of the day, there are N characters, each starting in their "home" location. e.g. Butler in Pantry, Groundsman in Garden, etc. This is denoted by hard-coded character tokens on the right-hand edge of the "dawn" board.
Each character has a strength and a dexterity. The ones with higher strength have lower dexterity, for balance.
After each hour, a character can only be carrying at most one object. If they die, they drop it.
Objects
More could be dreamed up, but how about, in descending order of priority:
Chocolate teapot: no benefit
Sword: Gives you the highest strength
Gun: May attack someone in an adjacent room instead of the same room
Armour: If you lose a fight, it is destroyed instead of you being killed
Rollerskate: Gives you the highest dexterity
The player's turn
There's a tableau of a few face-up cards to choose from. Player either picks one and draws a replacement into the tableau, or draws blind from the deck.
They place the card in an unoccupied slot. Until all H mini-boards have been placed, they may insert a new mini-board anywhere in the tableau, shunting aside adjacent events, and put their card on that new mini-board. Once all the mini-boards are out, they may only place in empty slots on existing boards.
They may only place a card in a slot for a room where they are at that time. (TBD: what if this is impossible?)
Then the timeline is fixed up to take account of the new event.
Events
Except where noted, the event is always performed by the player in the room who has the highest dexterity
Attack
Pick a fight with the player in range (your location, unless you have the gun) who has the next highest strength. They lose, and are killed unless they are wearing the armour.
If there is nobody in range with lower strength, pick a fight with a stronger character. You lose.
If nobody at all is in range, nothing happens.
Move
Move up and move down cards are self-explanatory. Move up can't be placed at the top of the board and move down can't be placed at the bottom.
Discover an object
One of these for each object. The object materialises in the room where the card is placed, at the time when it's placed. (It doesn't matter who discovers it, and the object appears even if the room is empty.)
Take
Drop anything you're carrying, then take the highest-priority object lying around in the room (which might be the same thing you just dropped).
Throw
Throw up, or throw down: drop anything you're carrying into an adjacent room. Similar restrictions to move up/down.