Blender has been discontinued and replaced with "Munchkin 7: cheat with both hands" http://www.worldofmunchkin.com/cwbh/
Seems like a must if you plan on mixing decks.
If you are starting with munchkin - I'd go for deluxe edition. For me, the most fun expansion seemed to be Demented Dungeons for adding nice mechanics.
And I really don't recommend mixing stock munchkin with star munchkin and any other theme expansions.
