Bit of an oddball build... Cleric 2/XX 1/Master of Shrouds 2/Ur-priest 2/Master of Shrouds +x/whatever else
I was ruminating (because I'm eloquent like that) over some monster classes to fill in the XX. Since I brought it up in another thread, I think a Lumi Ur-priest MoS would be interesting, both from a mechanics and thematic point of view.
With some psionics and incorporeality via another route, there's the
unbodied which could make for an interesting late game build.
Unbodied 4HD+4LA/XYZ 1-2/Ur-priest 2/Psychic Theurge 8-9
where XYZ is whatever you need to meet Ur-priest prereqs. Unbodied gets the bluff skill which is one of the more awkward prereqs to get. I don't have my books on me so I can't remember what else you need aside from a couple feats and the class needs to have a good fort save.
Another random idea going back to my original build: Go warforged and cap it off with Landforged Walker... so now you're a robot tree with undead minions. Start off with Cleric 1/Totemist 2... fill the rest as MoS 2/Ur-priest 2/MoS 8/LW 5, and you're a robot tree who channels magical beasts and controls undead. Heh, that sounds like fun actually.