Hi.  Just had to point out a hole in Keldon Elite's Inviolability (I checked the card, that's the spelling) article posted 8/17.  There are a few ways to kill a creature enchanted with Inviolability and Diplomatic Immunity-they don't target, and they don't deal damage.  This is assuming that the creature's controller can actually get both enchantments onto a creature without having it burned or killed in response.
Pernicious Deed, Wrath of God, Diabolic Edict, Nevinyrall's Disk, Rout, and Planar Despair (I think that's what it's called, it's the Sorcery from Apocalypse for 3BB that gives all creatures a -X/-X until end of turn based on your domain).