The third version of the Undying deck tried to mitigate a few of the issues the previous version encountered.  Geralf's Messenger is the workhorse of the deck so it's important to abuse undying as much as possible with it.  However, there was no good way of doing this outside of Carnifex Demon out and ready to go or a sorcery speed Black Sun's Zenith with X=1.  Fume Spitter was put in to take up this necessary role as well as provide more early presence and to deal with early creatures and utility creatures.

The lowered emphasis on green also made Thrun more difficult to cast.  Thrun also had a tendency to die at my own hand.  I replaced it with Phyrexian Metamorph in an attempt to undying mechanic when copying Geralf's Messenger.

Version 4: http://deckbox.org/sets/170722