The players then take turns writing a line until they get from start to finish. You can take turns writing lines, mini-scene descriptions, paragraphs, whatever - run wild! Go crazy! Have fun doing it, though, and feel free to use the Avengers Mansion Challenge! tag (see below) if you post anything that comes of it.
My friend valdemort and I played a few nights ago, then cleaned up the results and ended up with a lovely bit of fluff that we posted over on AO3. Feel free to give a look.
And I answered here with this:
So - I've been thinking about slash, and what makes it work for me. Of course, there's the general hotness of it, seeing men going mad with abandon, but there's two other big elements that do it for me.
First is the fact that it's there - hidden in the shows, just effin' waiting to be found and fed. Watch, for example, how Tony looks at Bruce while he walks behind him and shocks him - if that isn't checking someone out, I don't know what is. And Bruce likes it; he smiles, and sees. So it's like the writers are daring us to see this, as writers have been in Hollywood for decades. 
