Above you have put "Profound Journey/Sheoldred, Whispering One: Both of these serve to reanimate our graveyard. Can win us the game if used to bring back Test of Endurance or Felidar Sovereign during our upkeep."

Just to say that actually isn't possible, as I asked the question myself a while ago on StackExchange: Felidar and Sheoldred interaction

Loving the deck other than that though

Ryu Akamatsu: Thanks for the heads up! I haven't updated the deck in a while, but I've become aware of that mistake since then and have taken both Profound Journey and Sheoldred, Whispering One out of the deck. Thanks for reminding me that I desperately need to update this list. xP

Nice to come back and see this with the tweaks you've made. It's looking very good.

What do you think about swapping Phyrexian Gargantua for Harvester of Souls?

NoSoyYucateco: I've actually already replaced Phyrexian Gargantua with Rhystic Study. I've updated the decklist, now I'm going to work on updating the (horridly) outdated description. Thanks for the suggestion!

Ah, good. Rhystic Study is an excellent card.

Why do I never see wall of reverence? Amazing with serra avatar, you double your life each turn.

cypherrichard: I used to run Wall of Reverence, but didn't find that I was playing enough high power creatures to make it worthwhile. It would probably fit better in a Karlov of the Ghost Council or Trostani, Selesnya's Voice deck. Good card either way, just not for this deck.

Serra Avatar + Wall of Reverence

End turn, double your life total.