my idea is a god of war style hack n' slash, but with the size of the encounters matching up with fable 2. the protagonist would discover a curved sword where the top of it hooked forward, so there would be a combination of slashing and stabbing, and using the hook to grabbing enemies, flipping them on their backs, or throwing them at other enemies. the weird thing about the sword is that when it kills somebody, the killing slash or point of impact would emit light, and the person's soul (or spirit depending on what you're fighting) would ascend from their body through that area, by grabbing it with the hooked edge, the player could spend it on upgrades, if you don't catch the soul before it floats away, you get nothing.
the plot would be something like this, an immortal demon thing has enslaved humanity, its brainwashed guards do anything he says. the only thing that can kill him is the sword, which is discovered by a weak, near dead slave, the sword heals the user out of combat, but the healing properties are removed upon dropping the sword. the slave plots to overthrow him and save humanity. the thing is, once the demon guy is dead, the sword will disappear, knowing that it has fulfilled its purpose.
when you capture a soul, you have 2 choices of what to do with it when the encounter is over, free the soul, and only get half the points, or destroy it and get full points. it would all tie into a moral choice system where the swords attack style and appearance would change, also, destroying the soul will corrupt the protagonist, twisting him mentally and physically. the moral choice system would also lead to alternate endings where keeping the souls has the people who died go to a better place, along with the protagonist, who would die in that ending from being returned to near dead state again. or the souls are destroyed, and that person is removed from history and erased from memory, but the protagonist survives when the sword breaks, and becomes the new evil ruler of the land.
what do you guys think of that Idea?