Kieron Gillen: Down endings in PC games are an odd one. A few try them, and just end up stinking of nihilism. Others - and I'm thinking of the tragedy of Planescape Torment here - succeed beautifully. But, ultimately, if you're worried about it... why take the risk?

Warren Spector: Well, it's an interesting risk. I can't wait to see how people respond to it. At some levels, that's good enough. And Eidos trust me and my studio enough. We have a track record of not taking the type of risks that destroys us critically or commercially. Costing some sales is not the same as not being profitable. We're still clearly profitable and it's an interesting thing to try out. And it's not like these are down endings per se - these are all endings that follow naturally from the goals expressed from all the groups in the game. They are for the purposes of the game, how the world should look. We can't have infinite end games. The team didn't want to encourage one single ending - so we ended up with a bunch that made you think.