Personally, I find that Sign in Blood is lackluster in EDH. I think Read the Bones is potentially okay because of the scry. I would run Erebos, God of the Dead.

Dark Ritual is kind of the same thing. I'd rather have a continual use out of something, like Gilded Lotus, rather than a one-time effect. Doubling Cube for more mana, too.

I have a zombie deck, and one hilarious card in it is Gravespawn Sovereign. I've actually won with that card by sacrificing and repeatedly returning Gray Merchant of Asphodel. Plus, when you drop a card like that in EDH everybody is always like wtf is that and don't view it as a threat until it's too late. And it always stalls other reanimator decks late game.

I agree Sign in Blood isn't great, but it's a pet card in our group and always great when you can kill someone on their last few life with it. I like Erebos, God of the Dead, but since Kalitas is also a mana sink I'm probably going to pass on him for the deck.

Dark Ritual is a card I'm trying out. I like the prospect of casting Kalitas on T1 with that and Sol Ring, or casting something like a board wipe a few turns earlier than expected, so we'll see how it plays out. Gilded Lotus would be the logical swap for it. I'm not sure how I feel about Doubling Cube, but I'll keep it in mind. Gravespawn Sovereign is another card I'll keep in mind as I play the deck.

Thanks for the suggestions UpsetYoMama!

No Mercy

Yes Mikaeus gives all of your vampires/zombies undying, but it also gives them a +1+1 counter which makes it so that their undying won't trigger, so this is useless unless you have a way to remove the counter. (A Vampire Hexmage perhaps).

No Mercy is decent, but lends itself to a more pillowfort approach than I'm going for here. Something to think about.

Andrew6Gardiner, I don't think the undying is useless at all. Mikaeus, the Unhallowed gives your non-human creatures a static +1/+1, so the non-tokens still get an undying trigger before they get a counter. Since Kalitas will often have counters he probably won't get the undying too often, but will still get the static +1/+1 which is nice. Granted undying only triggers once, I could always run the Cauldron of Souls in my maybeboard to be able to repeatedly recur my creatures. But really, the prospect of triggering Fleshbag Marauder or Merciless Executioner twice in a turn is too good to pass up.

you should definitely put in Horobi, Death's Wail and abuse Cauldron of Souls and Touch of Darkness

I agree with the Cauldron of Souls. Combine that with your board wipes, and you'll have the game in hand.

I see the Horobi, Death's Wail + Touch of Darkness combo, but Cauldron of Souls would only work before Horobi drops, right? Otherwise my creatures die before the persist ability is applied. I have a feeling if I put Horobi in then Kalitas will be getting killed all over the place. I think I'm more convinced on Cauldron of Souls though. Anyone have suggestions for cuts?

Yes, just like Undying, Persist must be applied prior to the death of the creature (even if it happens on the stack above whatever's killing said creature.)

So it would work with Horobi to protect your own creatures if you tapped it prior. I was more considering Cauldron of Souls as a way to keep control of the table after using Damnation, Deadly Tempest and Necromantic Selection, and also a great way to keep your Commander alive if your opponent gets clever and indirectly targets your commander.

I agree on your reasons for adding it, they're exactly why I was thinking about it. I'll put it in the next time I'm swapping cards in decks...so sometime this week.

I'd be wary of adding Lifeline. It works so that if an opponent's creatures dies and you have a creature, say a zombie, they get their dude back.

I know it works like that NecroPony, but I figure with Kalitas out my opponents' creatures won't come back (since they won't technically "die") but mine will. Letting people abuse it is definitely something to watch out for, so maybe have a backup to Kalitas with Leyline of the Void? I might try it out next time I play to see how it goes.

+1 for the description alone.

I think it would be awesome to run old Kalitas, Kalitas Bloodchief of Ghet, in the deck too. I don't know what you would cut though.