Prison Break Simulator (not actual title, just a descriptor)
Remember the Great Escape game from 1986? Where you were a POW and had to come up with an escape plan, scrounge together the tools for the job, learn guard patrols and realize what items to take with you to succeed? That idea, on a larger scale.
In a medieval/dark fantasy setting, there exists the worst prison in the lands: The Pit. A former mine that stretches deep underground, now converted into the hole where the worst criminals and undesirables are thrown into and left to rot. Background, social status, gender, family status, The Pit doesn't care, there's room for everyone. It would have first- or third-person perspective and be an RPG in terms of stats, skills and "choice and consequences", but otherwise play similarly to the Gothic/Risen games, though with a more mature conversation system.
To begin with there would be three "classes", each representing the three major ways to beat the game:
The Brute, a large muscular man with battle scars and a constant scowl, he's in for multiple homicides, is a strong fighter and not afraid to kill. He would be the combat class and excel in that field, being even strong enough to take down a guard in a one-on-one fight. But a brute has to be smart to survive, know to pick his fights and go for quick kills instead of prolonged fights, else the guards will show up in force and toss him into solitary (if he's lucky). He would be minimal on interactions with the other prisoners (except to bash their skulls in) but would have the option of trying to rise up in the ranks of a prison gang instead of escaping, He could then take over a gang, then declare war on the other gangs and eventually, through sheer force, rise to become a kingpin within the prison, living the good life. You see, while escaping the prison is given as the "goal" of the game, the option to rule the prison from within will also be present in all cases.
The Rat, a veritable mouse of a man, thrown in for innumerable counts of theft, burglary and fraud, is the stealth class. His approach could be to either dig an escape tunnel for everyone, or become the Gopher of the prison, the guy everone comes to see for all their needs. Sneaking into restricted areas, nabbing keys and making copies, trading items and such. To become such a vital person within the prison that no one dares touch him.
The Leader, a charismatic good-looking man, locked up for treason and attempting to usurp the king or somesuch. A politician down on his luck, or someone trying to overthrow a tyrannical despot. He's the fast talker, the people person, the guy who greases other people's palms to get what he wants. His approach to escaping is through the other prisoners, making deals, forging alliances, giving orders, letting others do the dirty work and slowly turning the inmates into his own personal army. Whether he uses the army to rule the prison or to break out is up to the player. Hell, he might even manage to win the guards over to his side and they let him walk out through the front door!
Regardless of which "class" is chosen, the prison layout stays the same, but guard patrols and "rooms of interest" are randomized each time.
But here comes the controversial part that will make gaming journalism go apeshit bananas. Once a player has successfully beaten the game with at least two of the above classes, a new "class" is unlocked: The Woman. Anyone ever wonder what kind of game Gothic would be like if the protagonist was a woman? VERY DIFFERENT GAME. And being a woman in a male-centric prison presents a whole new set of challenges... and opportunities. Will you be the bitch that's passed around, or will you use your sexuality to have others do your bidding? In RPG terms, the Woman would be the Jack-of-all-Trades, free to adopt any strategy to achieve her goals, while possessing a unique "tool" that can overcome seemingly impossible odds.
Reading over what I've wrote, this game could also work with strong roguelike elements.