Be patient at the start of the game and build up a small defense of zombies. once you have lands in play you can go head first into doing what Varina does. Swing out with zombies. It's fine if they die (except the ones that give tribal buffs, keep them alive), because you'll get them back later. Use the card draw to find graveyard recursion like: Zombie Apocalypse, Unearth, or Phyrexian Delver, as well as any counter spells and good zombies. While doing this, keep throwing any big bombs and powerful Zombies in the graveyard. Once your graveyard is healthy in size due to all the discard, you recur your most powerful bombs (which one you get will depend on the situation) and start getting zombies out. If you can hold onto Zombie Apocalypse for very late game and cast it for over half the deck, you can basically end the game on the spot. Zombies are cool, which is why they can win without combat damage if they're put up against a stronger Tribe, like Elves. One of these ways is with Pingers like Wayward Servant and Vengeful Dead in tandem with board cleaners like Archfiend of Ifnir, Dictate of Erebos, and Noxious Ghoul. Using these two card types together can stagnate your opponents to a disgusting degree, and in some cases will effectively stop them from playing. This is especially effective when propped up with counter spells used only to protect your board state from removal or board-wipes.
What these cards are for:
Varina, Lich Queen; she generates the card-draw and discard that gets the deck running at full power, plus the life-gain keeps you alive for mid-late game where your huge spells can become overwhelming. After a certain set-up is achieved this deck will be able to draw it's entire deck and then reshuffle it every turn, gaining immense amounts of Life and allowing you to acquire any 7-card hand you want at any time,
Bone Miser; Gives value to Discard
Cemetary Reaper, Death Baron, Diregraf Captain, Gleaming Overseer, Lord of the Accursed, Undead Warchief, and Wonder; These cards, called Lords, provide buffs for your creatures and in many cases will keep them alive and attacking far longer than they could without these cards.
Corpse Harvester; use him to tutor up whatever Zombois you need and to avoid missing land drops. (Don't forget that Sunken Hollow is a Swamp card!)
Corpse Knight, Diregraf Colossus, Oketra, Noosegraf Mob, Noxious Ghoul, and Wayward Servant; these cards all benefit from getting zombies into play by pinging enemies, Weakening creatures, and spawning more Zombies!
Diregraf Captain, Plague Belcher, Syr Konrad, Undead Augur, and Vengeful Dead; When your zombies die, your enemies suffer (and getting those zombies back is easy anyways)
Diregraf Colossus; Big monster + Above
Fleshbag Marauder; once the deck is at full steam this card can be used to repeatedly kill off enemy creatures. If you're able to draw the entire deck in one turn and reshuffle it , then you will be able to cast this creature every turn at least 3 times.
Forgotten Creation; Use to dispose of unwanted hands and generate discard triggers.
Gisa and Geralf; Puts some cards in the graveyard (Hopefully Zombies), and allows for some strong recursion if you don't draw too much attention from the table.
Gleaming Overseer; Protects all those 2/2 zombois you're gana be making
Oketra; {BOMB} Double Strike Zombie with the ability to self-recur? EVEN OUT OF EXILE?! SIGN ME UP!!! + Above
Golgari Thug; feed him to Corpse Harvester as often as possible, and use his dredge to stuff your graveyard and recur him
Gray-Merchant of Asphodel; {BOMB} This card will win you games. Drop it as often as you can in mid-late game. Only play him in the early game if your opponents have limited exile options.
Havengul Lich; This card can steal activated abilities like Corpse Harvester's and Skirk Ridge Exhumer's. Use mostly as a second Corpse Harvester.
Josu Vess; {BOMB} Discard him if you get him early. Recur him once you have the 10 mana to pay the Kicker (3B+7 total), and if you get to do this, you will have a very powerful board state.
Laboratory Maniac; {BOMB} This card will win you games. Play this, the draw your entire deck with Varina triggers, and you win.
Lord of the Accursed; Gives your Zomboiz Menace + Above
Nimble Obstructionist; Counter Spell. Do Not cast this as a creature.
Noosegraf Mob; Makes Zomboiz
Noxious Ghoul; Kills Non-Zombies, even if they have Indestructible
Phyrexian Delver; 2nd Best recursion in the entire deck. Use to ambush the table with Gray-Merchant of Asphodel
Plague Belcher; First ability can be used to kill a Zomboi and get some death triggers + above.
Skirk Ridge Exhumer; Makes GobZombs that can be used for removal.
Syr Konrad; {BOMB} This card will win you games. Get him out and keep him out. Trigger him in as many ways as you can.
Unbreathing Horde; Big monster + Hard to kill with burn or combat.
Undead Alchemist; {BOMB} This card will win you games. Swing all your Zombois at one single opponent, to force them to mill as fast as possible, generating more and more zombois for you.
Undead Augur; Gets you cards.
Undead Warchief; The Best of the Zombie Lords, and makes Zombois cheaper to cast (and recast).
Vengeful Dead; Above
Wayward Servant; Hurts them and Heals you
Wonder; Discard this thing asap and get an Island into play (Remember that Sunken Hollow is an Island) to give all your Zombois flying.
Army of the Damned; That's a lotta Zomboiz!
Decree of Pain; Sometimes the world needs to be purged in order for you to get ahead of your opponents
Ghoulcaller's Chant; Recursion that works twice as well for Zombies
Rise from the Tides; Gets a ton of Zombois in the late game. Bonus! Got a huge graveyard while Varina and Elixir of Immortality are in play? Cast this, get Zombois, Go to combat step, trigger Elixir during Declare Attackers step to reshuffle your graveyard, then your attack draws you a bajillion cards, hopefully including Elixir and Rise from the Tides, go to Discard and throw away as many zombies as you can, repeat on next turn. Do this as many times as you can, because once you get this loop going you can redraw and reshuffle your entire deck every single turn. That means you can have a perfect hand every turn and pick and choose what creatures and spells go into your graveyard.
Unearth; Recursion for important creatures, like Lords and combo pieces.
Zombie Apocalypse; {BOMB} This card will win you games. Best recursion in the entire deck. Use with the loop mentioned above to massively boost your board state once enough of your deck is in the graveyard.
Countersquall, Countervailing Winds, Perplex, Render Silent, and Undermine; Use to defend your board from board wipes and spot-removal. Use these counters purely defensively.
Despark and Mortify; Use to take out important enemy combo pieces and bombs. Use these wisely as they could decide the game.
Shadow of the Grave; Use to mitigate early game discard and keep your hand at 7. Bonus! If used during the loop above, right after Varina causes you to discard, you will effectively draw your entire deck for the price of 2 mana during the opponent's Declare Blockers step, and will have your second main phase to win the game or do the loop again if you cannot win yet.
Liliana Vess; Discard, Tutoring, and Mass Recursion? Uh... yes... Use her to force opponents to discard, and to tutor up necessary cards. Only use the -8 if you can win immediately.
Liliana, Untouched by Death; Stuff the Graveyard, and cast Zombies from it, spot removal for dangerous enemies (use the -2 Sparingly).
Signets; They give mana
Bag of Holding; Allows you to mitigate early game discard by setting powerful cards aside in the bag and pulling them out as soon as they can be used in the mid game.
Bolas's Citadel; {BOMB} This card will win you games. When this card comes into play you change how you play this deck. You will cast as many things with the Citadel as possible before going to combat. Then resume the loop as above, this will rapidly cast your entire deck.
Coat of Arms; {HIGH VARIANCE} DON'T USE AGAINST OTHER TRIBAL DECKS! This card can instantly win you the game or lose you the game.
Desecrated Tomb; Tokens for free when using recursion? I'll take free tokens! I can Sac them to Viscera Seer or Corpse Harvester!
Elixir of Immortality; This card sets up many strong combos in the deck and must not be exiled. If an enemy exiles this card, you will lose access to several combos. Use to set up the combos listed above and any listed below.
Grimoire of the Dead; Mass Recursion and Discard triggers!
Mind Stone; Ramp and possible card draw in a pinch
Sol Ring; Ramp
Dictate of Erebos; Use with Sacrifice outlets to oppress your opponents. By sacking your 2/2 zombois you can easily keep the board clear at all times with this enchantment in play
Endless Ranks of the Dead; Either this baits out some targeted removal, or it gets you a very large board state slowly over time.
Faith of the Devoted; {BOMB} Use to ping enemies down after swinging with Zomboiz and getting tons of Varina triggers and discarding a ton of cards.
Liliana's Mastery; It's a Zombie Lord on an enchantment that summons 2 Zomboiz. That's value right there.
Necromancer's Covenant; Can spawn a ton of Zomboiz, Especially if you were able to use Noxious Ghoul or Archfiend of Ifnir to keep killing enemy creatures. ONLY TARGET YOUR OWN GRAVEYARD IF YOU KNOW YOU WILL WIN ON YOUR TURN!
Necromancer's Stockpile; Card Draw and makes Zomboiz, plus discard triggers. This card can be a massive value engine if you have the right board state.
Revel in Riches; {BOMB} This card will win you games. Alt win condition and Ramp.
Rooftop Storm; Free Zombies?! Heck YEAH!
There ya Go Levi! Hope you like it!