Necrotic Ooze–based combo decks have been the subject of some discussion, but they have failed to perform well at major tournaments. Fortunately, with the decline of Solar Flare, graveyard hate is declining as well, so this deck is well-positioned to take a lot of people by surprise at your local FNM. It packs some powerful creatures, but also a combo finish if your opponent deals with your other threats. Here's the list I've been working with:
3 Bloodline Keeper
3 Civilized Scholar
3 Reassembling Skeleton
4 Necrotic Ooze
3 Insatiable Souleater
3 Grimgrin, Corpse-Born
3 Mana Leak
4 Forbidden Alchemy
4 Go for the Throat
2 Nephalia Drownyard
4 Drowned Catacomb
3 Swiftfoot Boots
3 Armored Skaab
2 Doom Blade
Necrotic Ooze is the combo's killer. With Bloodline Keeper and Grimgrin, Corpse-Born in your graveyard, it can tap to make a Vampire token, then sacrifice that token to get a +1/+1 counter and untap itself, ready to repeat the process as many times as you want. If you don't have the combo yet but you have a Civilized Scholar in the graveyard, the Ooze can even loot repeatedly, letting you draw and discard cards until you can't discard a creature. This is especially valuable if the last combo piece is in your hand—you can discard it and have the Ooze untap itself, ready to immediately crush your opponent.
Aside from being part of the combo, Bloodline Keeper is a fine threat on its own. It can pump out a 2/2 flyer every turn, and if you manage to create four of these tokens, you'll be able to transform the Keeper and probably kill your opponent. An army of 4/4 flyers tends to do that.
Grimgrin, Corpse-Born is simply devastating if he ever untaps. Even if you don't have another creature on the board, most opponents will go out of their way to kill him, just in case you have a creature in hand. If you have a Reassembling Skeleton to go with him, you often won't even need to combo out.
Insatiable Souleater replaces Skinshifter as the card that lets the infinitely large Ooze give itself Trample. It also eliminates the need for the much more expensive three-color mana base. Trespassing Souleater is also an option, but the 5/1 body is often more than worth the extra mana if you ever cast it. Against control decks, it's a four-turn clock that your opponent simply has to deal with, which means he's losing a removal spell or a counterspell that could have been used on one of your more important creatures. Against aggro decks, it will either soak up a burn spell or trade with one of your opponent's best creatures.
Spellskite not only protects your other creatures, but it shuts down Kessig Wolf Run and Angelic Destiny. It necessitates yet another removal spell or counter from your opponent, greatly reducing his ability to deal with all your threats. Against aggro decks, it's even a fairly good blocker. If you can get your hands on a couple more of these, I highly recommend including them.
Reassembling Skeleton can serve as a recurring chump-blocker against aggressive decks, feed Grimgrin, Corpse-Born, or be sacrificed to Liliana of the Veil. It's also essentially a free discard to Civilized Scholar, since it doesn't cost any more mana to play from the graveyard than it would from your hand.
Civilized Scholar is a great way to dig for the combo and an easy way to put the pieces straight into your graveyard. Against control decks, it can also transform into a 5-power beater, creating another threat that the opponent has to answer.
Forbidden Alchemy is an amazing way to find the cards you need. Much of the time, the cards you put in the graveyard will do you just as much good as the one you put in your hand. The ability to cast it again doesn't hurt either.
Ponder is another good way to fix your draws, and the fact that it only costs 1 mana helps you cast it without setting back your game plan at all. This card has already proven its usefulness in multiple formats, and there's not much more I can say here.
Mana Leak helps to protect your combo and disrupts your opponent's game plan if you need a bit more time. Most opponents won't worry about playing around this because it quickly becomes obvious that you aren't playing U/B control.
Go for the Throat is the removal spell of choice here. Tempered Steel's popularity is on the decline again, while Olivia Voldaren's is quickly rising. Neither Doom Blade nor Victim of Night can deal with her, so Go for the Throat gets the nod.
Flashfreeze replaces Mana Leak against Wolf Run Ramp, since that deck can often afford to pay the 3 mana. The only spells it can't counter are Sphere of the Suns, Solemn Simulacrum, and Wurmcoil Engine. The first two aren't too worrisome, and the third hasn't been seeing much use lately— Inferno Titan usually serves as the backup threat.
Negate is a hard counter for control decks, against which dealing with removal spells and counters is the most important thing. Go for the Throat should be more than enough to take care of the few creatures those decks have.
Swiftfoot Boots protects your creatures from removal and also enables Necrotic Ooze to attack immediately once you have the infinite combo, thus removing your opponent's window to deal with the threat.
Armored Skaab helps ensure that you stay alive against aggressive decks while simultaneously bringing you closer to assembling your combo. Its 4 toughness is a lot, and that will be enough to stop most creatures in their tracks.
Grixis Control – Game 1
I lost the roll and kept a hand of three Swamps, an Island, Reassembling Skeleton, Forbidden Alchemy, and Bloodline Keeper. My opponent opened with a Darkslick Shores before passing the turn, and I drew a Ponder. I played my Island and cast it, shuffling away some Swamps and an Insatiable Souleater, and drawing an Island. I passed the turn. My opponent played an Island and passed back. I drew another Reassembling Skeleton, played my Swamp, and cast the Skeleton. I ended my turn, and my opponent cast Think Twice during my end step. He played a Swamp and passed the turn.
I drew another Forbidden Alchemy and attacked for 1 with my Skeleton. I passed the turn. My opponent cast a Forbidden Alchemy of his own at the end of my turn, putting a Swamp, Chandra, the Firebrand, and a Snapcaster Mage in his graveyard. He played Sulfur Falls and passed the turn. I cast Forbidden Alchemy during his end step, grabbing a Go for the Throat and putting two Swamps and a Civilized Scholar into my graveyard. I drew a second Bloodline Keeper, played a Swamp, and cast it. My opponent cast Think Twice in response, then let my spell resolve. I attacked for another 1 with my Skeleton.
On his turn, he played another Sulfur Falls, cast Galvanic Blast on my Bloodline Keeper, then cast Snapcaster Mage to flash it back for the kill. He passed the turn. I drew Grimgrin, Corpse-Born and cast him. I passed the turn. My opponent played a Swamp and passed back. I drew a Swamp, played it, and sacrificed the Skeleton to untap Grimgrin and give him a counter. I went to declare attacks, and my opponent cast Forbidden Alchemy. He put two lands and a Snapcaster Mage in his graveyard, then let me attack. Grimgrin killed his Snapcaster Mage and hit him for 7. I then cast Bloodline Keeper, which he Mana Leaked, and I passed the turn.
My opponent played a land and passed back. I reanimated my Skeleton at the end of his turn. I drew Necrotic Ooze and sacrificed the Skeleton to untap Grimgrin again. Realizing my opponent was at 11, I reanimated and sacrificed the Skeleton 3 more times, bringing Grimgrin to 11/11. I attacked, and my opponent cast another Forbidden Alchemy. He didn't find an answer, and he promptly died to the Zombie king.
−3 Mana Leak
Grixis Control – Game 2
I kept a hand of Swamp, Island, Nephalia Drownyard, Forbidden Alchemy, Swiftfoot Boots, Grimgrin, Corpse-Born, and Necrotic Ooze. My opponent played a Sulfur Falls and passed the turn. I drew a Drowned Catacomb, played it, and passed the turn. My opponent followed suit with a Drowned Catacomb of his own and passed back to me.
I drew a Reassembling Skeleton, played my Island, and cast Swiftfoot Boots. I passed the turn. My opponent played Darkslick Shores and passed the turn. I drew Spellskite, played my Swamp, and passed the turn. My opponent cast Think Twice during my end step. He then played an Island and ended his turn. I cast Forbidden Alchemy, grabbing another Forbidden Alchemy and putting three lands in the graveyard. I drew an Island, played Nephalia Drownyard, and passed the turn. My opponent flashed back Think Twice during my end step. He then played another land and passed the turn. I cast the second Forbidden Alchemy at the end of his turn, putting a Go for the Throat in my hand and another three lands in the graveyard.
I drew a third Forbidden Alchemy, played my Island, and cast Reassembling Skeleton. I passed the turn. My opponent played a Swamp and passed back. I cast Forbidden Alchemy during his end step yet again, this time getting a second Necrotic Ooze and putting a third copy in my graveyard along with a second Go for the Throat and an Insatiable Souleater. I drew Drowned Catacomb and played it, then cast Grimgrin, Corpse-Born. My opponent cast Galvanic Blast in response. I equipped Grimgrin with Swiftfoot Boots and passed the turn.
My opponent cast Geth's Verdict during my end step, forcing me to sacrifice my Zombie and bringing me down to 19. He played another land and passed the turn. I drew Ponder and cast it, drawing Bloodline Keeper and leaving Negate and Drowned Catacomb on top. I cast the Bloodline Keeper and equipped it with Swiftfoot Boots before ending my turn. My opponent played a land and cast Black Sun's Zenith for 3, killing the Vampire and any token I could have made in response. He passed the turn.
I drew the Negate and cast one Necrotic Ooze. It resolved, and I attempted to equip Swiftfoot Boots to it. My opponent cast Go for the Throat in response, and I passed the turn. My opponent played a land and ended his turn. I drew the Drowned Catacomb, played it, and cast Necrotic Ooze. My opponent cast Think Twice in response, then flashed it back. He then cast Mana Leak on my Ooze. I cast Negate on his Mana Leak, then equipped the Ooze with Swiftfoot Boots and killed him.
This deck is very good at demanding answers from your opponent, and with Doom Blade still being the predominant removal spell, some of his answers won't even work. The value of being able to play strong threats while still having a combo kill lurking on the horizon is enormous, and it makes any removal spell aside from Dissipate or Oblivion Ring somewhat of a liability. As long as you can keep threatening to take over the board or combo off, your opponent will have a hard time keeping up.
As always, if you have any questions or comments, you can find me on the forums under Twinblaze, on Twitter under @Twinblaze2, or simply leave a comment below.