Budget deck on MTGO, be sure to click optimize under the "Add to Cart" after you click the Cardhoarder link to view the accurate price which is much lower than the price given on TappedOut
Overview
A "casual" Shadowborn Apostle deck using the great Sek'Kuar, Deathkeeper to gain some value and have a lot of fun. The value from his ability is useful in this decklist because when you sacrifice the Apostles to summon demons, he gives you 6 3/1 creatures with haste for free. More importantly though, he gives you access to and which are surprisingly powerful in this deck, more than I realized it when I was first creating the deck. The strength (and fun) in these colors come from Bloodbond March, Nantuko Shrine and ETB effects such as Purphoros, God of the Forge and Impact Tremors. These cards will normally fly under the radar on your opponents' threat detector with the exception of the God, but believe me when I tell you they'll win you the game in a very entertaining fashion.
Mulligans
In your mulligans, ideally you want at least 1 Shadowborn Apostle and at least 2 lands with one being a Swamp or a land that can tap for black within your first 2 turns. It isn't the worst thing in this deck to miss a turn 1 Apostle so don't worry if you only have Vivid or tap lands for on your mulligan. Also, Skullclamp is a powerhouse so if you have it in your opening hand, make any excuse to yourself to not mulligan. This card can be used early on your Shadowborn Apostle to gain insane value, as you have around a 50% chance to hit another Shadowborn Apostle not even including your draw phase.
"But wait, why would we want our Apostles do die before we get all 6 to tutor? Isn't that setting us back?"
No, and that's where the beauty of this deck comes from.
Gameplay
Your goal early game is to either get 6 Apostles out and search your toolbox of strong demons to slap down for the situation, or use Apostles as chump blockers when you have either Bloodbond March or Nantuko Shrine, because the value these tokens will give you is insane when you inevitably draw into your next Apostle. The more Apostles in your graveyard, the better for these cards. Awesome enough, on your Bloodbond March proc you can spend so instantly sac your Apostles again to tutor for another demon, like Razaketh, the Foulblooded. How sweet.
After the game picks up pace, it's important to start getting your stronger cards out on the field. This would include ideally Phyrexian Altar, which is absolutely nuts with your token enchantments. In fact, Phyrexian Altar + Skullclamp
with either of the enchantments out basically wins the game. Your friends will only get fooled by the squirrels once though. This is because you can draw 2 cards with from Skullclamp to your lesuire, spend to cast 1 of the many Apostles you've drawn into which triggers Bloodbond March, Nantuko Shrine, hell, maybe even both, which gives you a bunch of 1/1 creatures to clamp onto. Do you see where this is going? With Purphoros, God of the Forge and/or Impact Tremors and/or Zulaport Cutthroat you're dealing a lot of damage to everyone, drawing a ton of cards, and getting an insane amount of tokens and/or Apostles and possibly healing. Then spend to sac 6 Apostles to go for a demon, yaddah yaddah, rinse and repeat.
Or if you miss your pieces, you can play Sek'Kuar, Deathkeeper and more Apostles to get a bunch of 3/1 hasty bois that can pressure your opponents very quickly. This route is also very scary with Bloodbond March and its ability to recur your Apostles for more sacs and more 3/1 hasty bois. Did I mention how good Bloodbond March is?
Apostle Tutors
Typically, your first tutor will be Razaketh, the Foulblooded because he'll let you tutor anything for the low cost of 1 creature and 2 life. There are some instances where a card like Sire Of Insanity will be a better play, but that's why you have demons for different situations. With Razaketh out and at least 6 Apostles in your graveyard, you can grab either of your enchantments with his tutor effect, play another Apostle, and go crazy. In other situations you may need to tutor that turn but you don't have a creature to sacrifice OR maybe you're unlucky and Razaketh is in your hand. In that case, you can go for Rune-Scarred Demon for an immediate tutor and a big creature. Sometimes it is best to wait to sacrifice your Apostles in response to someone's spell so keep that in mind. Unless you desperately need whatever demon you're looking for that turn, you can always wait until the end step of the opponent before your turn in order to basically get your demon at flash speed. This makes it very difficult for your opponents to react and you can always chump block with your Apostles and sac them in response or sac them when your opponent declares their attack at you and flip in a big 8/8 flier. The versatility of the deck is definitely the most fun aspect of it.
Removal
Also, the deck includes colors great for removal, so if you need more enchantment/artifact removal, it's very easy to find cards like Reclamation Sage or Naturalize and slot them into the deck. For creature removal though, cards like Archfiend of Depravity, Reaper from the Abyss, and deck:Torment of Hailfire (Torment less reliable) should do the job fine. Along with those, your sac outlets and enchantments such as Grave Pact should ideally be strong enough.
Remarks
Shared Animosity is on my maybe list, not only because of the Apostles but also because of the squirrels. Many games I'll have over 20 squirrels out and that card would be bonkers in those situations. My only issue is that it seems more like a "win more" card than a necessity, but I'm still on the fence about it.
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