The new Delta Green series from Arc Dream has redefined the production standards for RPGs. Taking what was already a popular and exciting setting and then upping it to the next level in terms of artwork, layout, design . . . all intended to enhance the feel and mood of the game.
Impossible Landscapes takes this to another level still. It was already a complex and advanced way to treat Hastur, Carcosa and the King in Yellow besides being 'just another tentacled beastie' . . . the existing Delta Green take on this part of the mythos was to portray it as a subtle cancer on reality: an example of surreal horror as normality and rationality starts to crumble and give way. The book itself treads a narrow path between a game supplement and evocative manual, the very design of which starts to mirror the breakdown of reality as players progress through the campaign. Hints of madness almost creep off the page with the marginal scribbles and the disturbing artwork from Dennis Detwiller, that can be both photo-realistic and chillingly surreal.
It's a monster of a supplement (figuratively and literally) and you can tell that many, many weeks of effort, sweat and tears have been poured into it to update the ideas and original adventure (Night Floors) into the polished format and integrate with the other material. And in reading through you are drawn into the weird, fictive half-life that the survivors and refugees from Carcosa are drawn into. A bit like Arthur Machen in 'Baghdad', or Samuel Beckett's Malloy and Malone, there's a slight worry that after too much reading you'll start to see these characters pop up in real life, or merge into eachother. If DG were real, this book would be categorised as hazardous and there would be cells chasing down copies for eradication.
The bar got set high by the Agent's Manual, then blown out of the park by the Handler's Guide. This is going to be one of those supplements that people remember as being a milestone for RPGs, let alone the particular system it's written for.