Seems very black-heavy right now. I notice in your recent update you took out both Hedron Crab , and Paranoid Delusions both of which I would consider strong cards in the deck. I know you are looking at this as an opportunity for a Zombie tribal deck, but at the end of the day Grimgrin, Corpse-Born decks are always going to be strongest for that. I've lost to them enough to know. What I see with Sidisi is a really strong opportunity to take all the self-mill mechanics (Dredge, Scavenge, and now Delve) and put them in a single solid deck. If you run some things like Nature's Spiral and Treasured Find to get back things you might lose; Diabolic Tutor , Jarad's Orders , and other tutors to get key pieces; and maybe things like Elixir of Immortality for reset options, and you're able to cycle through your deck and graveyard pretty effectively, which will just spawn zombies all the while. I'd keep some zombie tribal cards in there to boost your tokens, but getting overly fixated on it probably isn't your best option.
kamarupa yes, the combo relies on Deathrender , but for this reason I have an aggro deck with undying to survive and I can use Nature's Spiral to bring Deathrender or any strong creature back to me. Unless it, I have 1-3 drops only, what I think is ok to support the game even without the combo (Rancor + undying is a good combo too).
I'd say your Avg. CMC is too high. Replace eight 4+ CMC cards with 1-2 CMC cards. If you're sacrificing a lot, then something that interacts with your Graveyard is going to add a dynamic to your game. You might consider some thing like Mending Touch or Nature's Spiral . Diabolic Servitude also comes to mind. There's a lot of others, just depends on what you'd like to add using all those cards going in the Graveyard.
Removal could pose some threats to your win. You might consider sideboarding a some of these:
An alternative to those would be Alpha Authority .
Personally, I really like using Proliferate as an added win-con. Contagion Clasp or Thrummingbird are affordable options in both cost and CMC. I run Contagion Engine in my Infect deck, but it's meant to run a lot slower than this.
I'm going to give a list of cards you should cut then add some similar ones nest to it. I don't know if you want budget options or not but ill try to stay cheap. (i assume you do)
Nonbasics (all for color fixing)
Shadowmoor/Eventide filter lands Twilight Mire and it's ilk
"tainted lands" tainted forest.
pain lands Brushland and it's ilk
the rest of the temples and guildgates that are in your colors.
Shocklands if you can get them IE Godless Shrine
Cuts & there replacements
While i realize this is a lot of change i tried to play into your deck's theme all my recomdations are under $5 (except when marked). so you have that going for you. I also don't know if you still care about the deck because the last update was a month ago.
I love monstrosity and this deck does well with it
Few notes: your hub says that the deck is in standard but Nature's Spiral makes it illegal
Cut the deck down to 60 cards and be more constant with the cards 1 ofs lower down the chance of drawing the cards you wAnt
Come check out my deck DETHRONE THE KING comment and +1
|Avg. draft pick||6.91|
|Avg. cube pick||11.35|
|Commander / EDH||Legal|
|2011 Core Set||Uncommon|
|2010 Core Set||Uncommon|