I posted a while back on a game that would be played with a character bereft of a memory of recent, climactic events. While planning, I came up with the idea to dole out information to the player by means of a dreams and half-recollections triggered by looking at seemingly mundane objects.
Concerning the dreams, I was thinking of implenting something of a dream world where the player can interact and advance dreams by wisdom checks; only under certain circumstances would I let them directly interact rather than passively observe. For example, let's say the character has been having the same dream now and anon for the past fortnight, with it ending each time after a walk down the same hallway, at a closed door. I might let the player open that door with a Wisdom check, and even if they fail, maybe if they roll high enough, I might uncover some detail that was previously unnoticed. The player would only be passively observing in this instance. I would essentially be revealing more and more layers of the dream to the player.
But, I was also thinking that dream combat would be, to be frank, kickass. I might let the player summon up dream weapons or equipment with a Wisdom check; normal movement could be flouted, with a Wisdom check; death, as far as death could go in a dream, could be shunted with a Wisdom check. There would of course have to be restrictions on these things, such as number of Wisdom checks used towards special actions per round, and exactly what the limits of power would be, but I think it would be the funnest thing in the world (I was totally into Nightmare on Elm Street). I might even have an extended foray into the dream world where direct interraction would be possible at all times; this might be brought on by a comatose state rendered by a head injury or something.
For rules, I was thinking a number of Wisdom checks per round equal to the (Wis modifier)/2, with one being the minimum. This also might improve over time, with maybe one bonus usage added every 2 or 3 levels of consistent usage. For limits of power, those would just have to be eyeballed with discretion by me. Also, I use the Wisdom check because it's simple and ready at hand. Moreover, I'm not going so much for rigid rules as I am a loose model that would let me flow with it, in a manner of speaking.
So, what say you folks? Any suggestions would be greatly appreciated.