There are lots of ways to abuse Heartless Summoning(Easily my favorite enchantment in Magic) in Modern, usually involving an endless "recycling" loop with two Myr Retriever. For those who don't know yet, they become 0 mana 0/0's that die instantly upon entering the battlefield, and when they die you can bring a Myr creature to your hand, target your fallen Retriever and repeat process. A few cards can really abuse this, my favorites being Altar of the Brood to consistently deck your opponent out whenever a retriever successfully enters, Falkenrath Noble for an endless life drain combo(opponent loses 1 and you gain 1 each time one of your creatures dies), and Grim Haruspex for an endless draw combo(draw 1 whenever one of your creatures dies). This particular build utilizes Altar of the Brood and Grim Haruspex, as it opens up potential for a turn 2 win.
Turn one: Land, tap 1, Altar of the Brood. Turn two: Land(Black if you didn't play one last turn), tap 2, Heartless Summoning, Myr Retriever for 0 mana, opponent mills 1, Retriever dies, Myr Retriever for 0 mana, opponent mills 1, Retriever dies, return retriever from graveyard to hand, repeat process maximum of 52 times for game.
This is assuming the opponent is using the minimum 60 cards of course, but the deck count just makes the process take more time/less time if your opponent makes you play it all out.
Needless to say, this play won't always work and only goes off on turn 2 if you have that perfect opening hand. So, lets go into the rest of the deck.
I briefly went over how awesome Grim Haruspex is for decks based around Heartless Summoning, so re-explaining how it works is a bit redundant, Haruspex is a 1 black mana costing 2/1 that lets you draw every time a creature of yours dies. You can use this exploit to cycle through your deck to reach your win condition if you don't already have it, and grab the counterspells and removal spells you might need for the situation.
Havengul Lich, while slightly less reliable than two Myr Retriever creates an endless recycling combo of its own with Myr Moonvessel while Heartless Summoning is active. While Heartless Summoning is out, Havengul Lich is a 3 CMC 3/3 creature, and the problem with that towards the combo is that it is within killing range of Lightning Bolt, arguably the most powerful, most commonly used and most mana cost efficient burn spell in Modern. But, if you pay 1 mana and target a Myr Moonvessel in your grave, you can bring cast it from your grave for 0 mana, have the opponent mill 1 from Altar of the Brood, have it automatically die and get 1 colorless mana, then use that mana to repeat the process 51 times maximum(assuming this is turn 3, earliest moment you can play the Lich) for game.
Mulldrifter is a really cool card with Heartless Summoning. Evoke also applies to the Heartless Summoning cost reduction, making the thing a 1 blue costing 1/1 that lets you draw 2 before having to sacrifice it. Not only is that not an issue with heartless summoning killing the fish anyways, but it also triggers grim Haruspex which essentially turns mulldrifter into Ancestral Recall, drawing 3 for 1 mana. Who doesn't want that in their deck?
Perilous Myr is another weird 0 mana card that auto dies with heartless summoning, burning the opponent(or one of their creatures if need be) for 2 damage and giving you another draw with Haruspex and another card milled from the Altar.
Mana Leak and Spell Pierce are pretty self explanatory, classic counterspells are a great way to ensure your combo goes off interupted if it comes out mid-late game.
Dismember is another very cheap and versatile removal spell, much like lightning bolt. It's serving a dual purpose in this deck, being essentially a 1 mana way of getting rid of something an opponent has that's hurting you, OR you could kill off your own Grim Haruspex in a pinch if it's threatening to make you draw out your deck before your opponent's gets milled.
Fabricate is just kind of there to search out Altar of the Brood if need be, but more than 2 copies of it can just get in the way of other things you need to draw into. Having it there just gives you a potential reason to keep a hand you otherwise wouldn't, having the assurance of a way to grab it.
The sideboard is essentially just more utility if you need it. Spellskites are 0 costing with Heartless Summoning that can redirect a spell that would otherwise get rid of Heartless Summoning or Altar of the Brood, which you need to stay on the field in order for the deck to work properly. Relic of Progenitus is a classic Modern Sideboard card that really hurts decks that utilize the grave often, as well as cutting Tarmagoyf down to a much less threatening level. Thoughtseize serves as an anti control card and gives you a similar effect as the counterspells, keeping your win condition from being disrupted. More copies of spell pierce is great if you feel like you need more defense against certain matchups. Surgical Extraction tops off the deck, providing a means of erasing anything you mill that you're really afraid of showing up again and stopping you.
Hope you guys enjoy the deck, feel free to leave feedback or suggestions.
