2/25/20:  V10 --  Update.  Added Archon of Falling Stars, removed Cavalier of Dawn (how did I miss this recursion before!).

2/21/20:  V9 -- Update.  Need a sac outlet just in case coin creatures are not killed.  Want to add in Woe Strider, but not sure what comes out (Knight of the Ebon Legion?).  Added in Woe Strider, removed KotEL.

2/17/20:  V8 -- Update.  Removed Witch's Oven (did not seem very useful), added in Birth of Meletis.  Added in 1 Ethereal Absolution for those pesky mono-red decks.  Wondering if Forever Young would be a viable option; if so, unsure what it would replace.

2/15/20:  V7 -- Update.  Added in Castle Locthwain (need the card draw!  How was this not added in before?).  Added Eidolon of Obstruction (planeswalker disruption) and Hateful Eidolon (fits enchantment creature role for one mana, but no auras in deck -- not sure if it would be worth the addition?) to maybeboard.

2/14/20:  V6 -- Update.  Removed Teysa Karlov (does not work in the assumed way -- multiple triggers occur, but cannot double exile a creature to get double tokens!).  Removed Eat to Extinction (too slow, but may be revisited again).  Removed Witch's Cottage and Temple of Silence.  Added in Knight of the Ebon Legion (needed another good 1 drop) and Fabled Passage.  Wondering if Birth of Meletis would be a good addition (can fetch some lands if needed, provides solid blocking for aggro decks).  Not sure what would be removed -- Plaguecrafter?  BoM does not seem to have much use beyond that along with putting a +1/+1 counter on the Mystic.  Removed Plaguecrafter (didn't seem very useful).  Added in Elspeth Conquers Death. 

2/1/20:  V5 -- Update.  Added in Teysa Karlov for more janky goodness.  Wondering if Eat to Extinction should be replaced with Murderous Rider.

1/20/20:  V4 -- Update.  Replaced Yarok's Fenlurker with Doom Foretold.  DF was part of the initial combo, so removing it does not feel right.  Replaced Murderous Rider with Eat to Extinction.  Added Teysa Karlov to maybeboard (double death triggers could be massive).

1/18/20:  V3 -- Update.  Well, found out that you cannot exile a creature with Nightmare Shepherd then bring them back with Athreos if they have a coin counter.  Oh well.  Can still utilize both effects for different creatures.  Alseid is a solid addition.  Replaced Doom Foretold (still think it would work well in this deck, just seems a bit slow -- will revisit at a later date) with Eidolon of Obstruction (will see how it goes -- depends on amount of planeswalkers in meta).  Replaced Eidolon of Obstruction with Yarok's Fenlurker.

1/17/20:  V2 -- Updated.  Removed Cavalier of Night and Witch's Vengeance.  Added in Alseid of Life's Bounty (aka Gods Willing on a creature-stick).  Ayara also does not seem to fit here, so considering swapping her out, but not sure for what just yet -- maybe Plaguecrafter, Woe Strider, or Kunoros Hound of Athreos (not sure if the latter would mess anything up).  Removed Ayara, added in Plaguecrafter.  Yarok's Fenlurker is also a possibility instead of Plaguecrafter, as is Midnight Reaper for the card draw.  Added a bunch of cards to the maybeboard that have ETB effects or graveyard hate (Kunoros).

1/16/20:  V1 -- Created.  Idea is to recur Cavalier of Dawn and Doom Foretold with Nightmare Shepherd and Athreos; can also recur Cavalier of Night along with other creatures.  Athreos puts a coin on a creature (CAN BE OPPONENT'S TOO!), Ayara or oven can be used to sacrifice it.  Both Athreos and Nightmare Shepherd abilities proc; make sure to put the Shepherd's ability ON TOP OF THE STACK to exile the creature, then bring it back to the battlefield with Athreos.  Double ETB effects for said creature. Starfield Mystic to help reduce the costs of enchantments (remember, Nightmare Shepherd and Athreos are considered enchantments!), Idyllic Tutor to search for said enchantments, Doom Foretold for opponent's hand/permanents disruption (Athreos can bring back opponent's creature if selected), Cavalier of Dawn can bring back any enchantment from the graveyard when it dies.  Cavalier of Night can destroy opponent's creatures, can sac own nightmares or other cavaliers for recursion effects.  Witch's Vengenace (name "Golem") to kill off all of opponent's permanents-turned-to-golems.  Murderous Rider to handle any planeswalkers or creatures.  Ayara for card draw and life gain (assuming nightmare tokens are black?); Midnight Reaper could be an option as well, but loss of life makes it suspect for use.  Added Despark for permanent removal, Archon of Fallen Stars for graveyard enchantment retrieval to maybeboard.