I'm thinking of making use of the rock-paper scissors mechanism, where all players place a face down card every turn. When those are revealed a complex evaluation system translates the card combinations into game effects for the players.
One example would be a kind of hybrid between the card game "family business" about mafia gangs and the board game "Hoity Toity" (?!) (in german: "Adel verpflichtet") about art collecting nobles.
Each player runs a mafia gang in the '30s with different specialists: 1 boss, 1 club chef (=bosses right hand), 1 hitman, 3 mobsters, 1 lawyer, 1 bookkeeper, 1 forger, 1 informant, and a small set of one-use action cards like e.g. Vendetta, Razzia, F.B.I. and maybe others.
Every turn one of these cards is played face down by each player. The number of players is fixed, maybe to six. Decks not used for absence of players are shuffled before each turn and contributing 1 card from each deck dealt face down at random. When all cards are placed, they are revealed and the outcome evaluated. This would be handled by the core section of the rules.
No matter how the cards exactly interact, and in what sequence, the outcome is always that the players either loose played cards or sometimes regain cards from their lost piles. In addition to this players can make or loose money, or pay money to trigger effects, based on the abilities of their cards played, or force discomfort on opponents. The last ingredient for the bout are reputation points, which represent how much in awe other gangs and even official prosecutors are of your public image, your offers that can't be denied, or simply the proofs of your inescapable wrath. Gaining or losing reputation points can also be the outcome of the showdown for some players, mostly when they involve their heavy weights including their lawyer.
The boss card cannot go bust in any given constellation but it can't be played with zero or less reputation (players start with a nonzero value). Presumably the boss is in jail or hiding in such cases. Let the lawyer or bribing specialists do something about it, or turn to bossless strategies (should be rulewise implemented as more delicate, but possible).
Game winner is determined after a fixed number of turns, or after a turn some player runs into a remainder of mere three cards in his/her hand. Winner is the player with the highest combined total of reputation, money and point value of remaining personnel in hand.
Of course this is only a bit more then the naked game mechanism, but I think it's got substantials already, that might spawn ideas of concrete realization.
For my part, I give this concept as a free game idea. I don't expect any reference from people deciding to work with it. Feel also free to change theme as you like.
Let's stick to a hand of aforementioned personnel plus 3 FBI cards named FBI homicide dpt., FBI vice dpt. , FBI tax fraud dpt., and drop the number of human and automated players to five.
In sample turn there comes up 1 boss, 2 "FBI homicide dpt", 1 "FBI tax fraud dpt", 1 mobster. A sample outcome would be deducted from "the LAW". "The LAW" is the collection of evaluation rules to determine the outcome of any given turn, the combination of 5 revealed cards.
LAW (some number) says: If there are three ore more FBI cards revealed you have a "major razzia".
Every player, that has not revealed an FBI card loses 2 reputation per FBI card = 6 in this example. Every player that revealed his boss loses 10 reputation points (would have gained 5 otherwise). However, every player that played an FBI card in this excesss situation also loses 4 reputation as still running a gang and playing with fire (would have lost none with only 2 or fewer FBI cards revealed).
In addition to that other LAWs apply, like any player having a hit man or mobster loses 4 reputation on every "FBI homicide dept" card. The same goes for any "right hand" (= the club chef) on any (copies don't matter) "FBI vice dept." + 600 $ loss on alcohol sales. Another LAW enforces 600$ loss on at least one "FBI tax fraud dpt" for any gangster placing player, 1000$ if envolved in a "major razzia", doubled amount if unfortunately placing his bookkeeper. However, having a lawyer or informant still in hand halves all sums.
If you've played a lawyer you might be able to cancel some minor LAW against you, but not a major one like "major razzia".
One the other hand more lawyers than FBI cards revealed discard these FBI cards as "tax money is wasted to harass honorable tax payers doing sober business". Very bad FBI publicity.
Yeah, this is a democratic game (of crime). The majority is always right. Thus says the LAW.
Okay in a full fledged game the LAW can be very complicated (after all, I'm german). Probably a lot of game testing will be necessary to balance this core element. Maybe there coulb be developed a step by step resolution, that doesn't fail to execute every applicable LAW.
To evaluate the result of the given sample turn is left to the reader. It's only a fantasy example, so it's presumably not of much concern to calculate this one.