If it had no counters on it when it died, you can remove the counters and have the undying effect multiple times, its a trick that's been around for quite a while. but I do like your choice of Dark Ritual better for this deck.
Permalink
Undying Evil can only effect Xathrid Demon since he's the only creature without Undying so probably 8 out of 10 times you draw undying evil it will be pretty useless until Xathrid is out. if you use Hex Parasite you can remove the +1/+1 counters from your creatures so that they can use the undying effect more than once. or if you don't want to use Hex Parasite find something else that can be useful lol
have you thought about Hex Parasite instead of Undying Evil because I haft to agree with @Some_Soggy_Tacos on it seaming pretty worthless in this deck.
too much red ramp, I'd try lowering the number down, I'd drop Geosurge for two more Seething Songs and 2 Fireballs to deal more direct damage or help clear the field a bit.
most people don't think about it but Hellcarver Demon could be amazing in a Shadowborn Apostle deck
not bad but your not really going to get anywhere without pump spells, you've got a lot of creatures but that can backfire if you draw the wrong creature at the wrong time, check out mine and give me your opinion, I've changed a lot of things in it so the comments aren't accurate anymore lol http://www.mtgvault.com/morrius07/decks/spread-the-infection/
too many 5 drops and not enough sac targets
Bloodlord of Vaasgoth and Feast of Blood, add another Kalastria Highborn and another Bloodghast, remove 1 Pawn of Ulamog and add 2 Bloodline Keepers
I'd replace Mark of Mutiny with something else since you have Traitorous Blood and I'd two more reverberate, maybe replace Mark of Mutiny with Slagstorm.
why Treacherous Pit-Dweller? if you sac him your opponent gets control over it
Elspeth, Knight-Errant
you need Predator's Rapport, combos amazingly with Tree of Redemption
not exactly, only does 9 damage
only basic lands are allowed more than 4
but you can only have 4 of any card lol
no problem, im glad i could help, you still have 5 maze's end though lol
if you take away 2 Saruli Gatekeepers and add 2 Tree of Redemptions Predator's Rapport would be amazing in this deck, 26 life thank you lol
also Chromatic Lantern or Prophetic Prism could help
your lands should look something like this, this list should also let you splash red for all the awesome Izzet colored draw cards like Mercurial Chemister :) Azorius Guildgate Boros Guildgate 2x Dimir Guildgate Golgari Guildgate 3x Gruul Guildgate 3x Izzet Guildgate 4x Maze's End Orzhov Guildgate Rakdos Guildgate 2x Selesnya Guildgate 4x Simic Guildgate
needs more cards that create tokens, you also have way to many cards with high mana cost.
21-40 of 67 items