Arkham City PC Pre-order and release date

[TheWonko]

Looked around, didn't see anything about this.

Steam pinged me and told me that I could pre-order Batman: Arkham City [http://store.steampowered.com/app/57400/] for $49.99, or 20% off ($39.99) if I owned Arkham Asylum or LEGO Batman.

More importantly, it told me that the game will be released on 15 November. Less than a month for more Batman. Colour me excited.

 

[Hiphophippo]

I can't seem to find an answer to my question about this, which really I suppose tells me all I need to know here, but it's worth asking anyway.

"Is that 20% off PER each of those games that I own or is that a flat 20% off whether I own one or two?" Because if it's per game....