And then one day...

[skeloric]

You are almost ready to start a game of TORG (Yes this may be a bit of a stretch for most of us...) when a player suddenly sets before you a proposition that they will be the sole representative of a Cosm that they wrote up themselves or that they found online somewhere.
You could refuse outright but it could lead to arguing rather than gaming.
Instead you... [fill in the blank]

[hellsreach]

You are almost ready to start a game of TORG (Yes this may be a bit of a stretch for most of us...) when a player suddenly sets before you a proposition that they will be the sole representative of a Cosm that they wrote up themselves or that they found online somewhere.
You could refuse outright but it could lead to arguing rather than gaming.
Instead you... [fill in the blank]

Take a look at the cosm as written and see if it works within the power framework of your possible game. Adapting so some strange player ideas can be difficult, but it can also make for a rich and memorable game. If the cosm as written makes the PC to powerful, them explain that you'd like to tone things down. Work with the player so that he or she understands why it is game breaking or might disrupt your campaign.

Don't say no outright, at least not without trying to find a compromise, as few players find authoritarian GMs fun to game with.

[Stormchild]

I only had this once, a player who wanted to play a character from Melnibone (Elric's world by Michael Moorcock). For convenience sake, I gave this world only Axioms and no world laws. I don't know what Axioms we agreed on, but it was a quick one. All below Aysle except for Spirit which was higher. Magic done by conjuration substitution with Spirit. It worked without a problem. Though you could call it a problem that in High Lord of Earth, when the Darkness Device tempts the Storm Knights, he shouts "Blood, Souls and a Darkness Device for my Lord Arioch", Arioch appears, takes the Device and vanishes.

[The Game Guy]

You are almost ready to start a game of TORG (Yes this may be a bit of a stretch for most of us...) when a player suddenly sets before you a proposition that they will be the sole representative of a Cosm that they wrote up themselves or that they found online somewhere.
You could refuse outright but it could lead to arguing rather than gaming.
Instead you... [fill in the blank]

Well I know I am going outside of the spirit of the thread but have you had this happen to you Skeloric?

[skeloric]

Well I know I am going outside of the spirit of the thread but have you had this happen to you Skeloric?
Nope, its just an RPG exercise.
And an excuse to get a TORG discussion going.