Fight for your survival and perhaps the Multiverse itself in the War or the Spark by battling this Nicol Bolas zombie Horde deck alongside 1-3 of your friends in this cooperative format (read an overview of the format rules here). The 60x Walking Corpse are War of the Spark 2/2 zombie tokens with no abilities.
Borrowing from Pandemic, the Villains - Nicol Bolas (and the God-Eternals, if those are being used too) - are meant to be distributed somewhat evenly: Take them out of the horde deck, shuffle the horde deck and split it into five piles, then shuffle Nicol Bolas into the last pile. This will serve as the bottom of the horde deck. If the God-Eternals are being used, shuffle one each into the remaining piles, then stack them on top of the bottom pile that has Nicol Bolas in it. An alternative version of the deck uses both Nicol Bolas, God-Pharaoh and God-Eternal: Following the above directions, the God-Pharaoh is shuffled into the final of the five piles; the God-Eternal is not shuffled in but just placed as the last card in the pile. When playing against the Horde, the God-Eternal is only cast once the God-Pharoah is defeated or God-Pharoah gets sufficient loyalty to remove itself from the battlefield by using its ultimate.
Other too-powerful cards such as the God-Eternals, the huge card draw of Apex Power, the life gain cards such as Cruel Ultimatum, repeated recursion of Eternal Taskmaster, copy effects of God-Pharaoh’s Gift and Hour of Eternity, tax effect of God-Pharaoh’s Statue, and potential for immense life loss from Throne of thr God-Pharoah mean that I included potential replacements in the Maybeboard in case the Horde needed to be depowered somewhat. Also, 10x of the 60x 2/2 zombie tokens should be replaced with 10x 4/4 zombie warrior tokens with vigilance to make the Horde more alike the original one created and tested by the format creator.
A final option to increase the difficulty is to increase the number of cards that are revealed and cast by the horde deck. Instead of only revealing cards until a nontoken is revealed, whenever that nontoken is a God-Eternal, an additional 1 card should be revealed and cast, whether a token or nontoken. The rules could continue to be tweaked to make it harder and harder: Perhaps instead an additional card is revealed for each God-Eternal ever cast that game, even if they are no longer in play - at the end of the game, if all 4 God-Eternals have been cast (and not first milled from damage), cards would be revealed from the top of the library until a nontoken card is revealed and then a total of 4 additional cards would be revealed and cast. This idea is borrowed from a similar one from The Mana Base using the ‘[Planeswalker’s name] Defeat’ cycle.
There are a few alterations to the Horde Magic rules that I find to be necessary: 1) So that spells with X in the mana coat work as well as creatures with activated abilities, track of the turn count, and the horde deck can produce X mana of any color, where X is the turn number; lifegain causes the cards from the graveyard to go on the bottom of the library (either choose randomly or just begin with the bottom cards in the graveyard, to avoid recycling cards that were just recently played).
A potential add to the flavor is in the Maybeboard: For any players interested in the flavor of the Horde experience, the ‘Flavor’ cards of the Maybeboard could be reviewed before beginning:
Bounty of the Luxa and Renewed Faith establish the beauty of
Amonkhet and that there are Gods that are worshipped here. Trial of Zeal and Final Reward show one of the ways the people or the plane show their devotions to these Gods, which result in the ‘reward’ of being embalmed for those who are the strongest, smartest, fastest, etc. Approach of the Second Sun and God-Pharoah’s Faithful suggest that the evil, elder Planeswalker Nicol Bolas is somehow involved, and he makes his move in Imminent Doom. Most of the Gods are slain (Bontu’s Last Reckoning, Kefnet’s Last Word, Oketra’s Last Mercy, and Rhonas’s Last Stand). Nicol Bolas calls up the army of the dead he amassed out of centuries of the most honored of Amonkhet’s dead being prepared for this moment (Honor the God-Pharoah), they travel to Ravnica via a planar portal stolen from Kaladesh (Emergence Zone) and they attack (Invade the City). It’s now up to the survivors to launch a counterattack (Storm the Citadel) to prevent Bolas from restoring his god-like powers from before the Mending, which he plans to do through The Elderspell, which will despark his Planeswalkers enemies and combine their strength into his own. If the survivors can defeat the elder dragon planeswalker and his horde, the final two cards are revealed to show that Nicol Bolas becomes locked in his Prison Realm and there is a Planewide Celebration.