Eldritch Apocalypse is all about that 'infinite' token combo. And it's all about killing everyone else by turn seven at the latest. So, this is fairly straightforward. It combos Spawnsire of Ulamog with cards that improve the mana returned from using its first ability (e.g. Parallel Lives to obtain four tokens for four that sac for a total of C apiece, or Ashnod's Altar to let your pair of tokens sac for CC apiece) to set up an infinite token-creatures-enter-the-battlefield combo. Either pair works. Your outlets are Impact Tremors and Altar of the Brood. There's your primary wincon.
Next, we've got cards to get us there. Our main sources of chump blockers are Eyeless Watcher ,
Emrakul's Hatcher
, From Beyond , and Awakening Zone . These cards are all here because they are really good at giving us those puny little Eldrazi Spawn and Eldrazi Scion tokens, which add up fast over a couple turns. Eyeless Watcher can be cast on turn three if you've got Eldrazi Temple in play, and From Beyond is best spent when you've got the token base you want, but need to pop a Spawnsire into your hand, just in case. Emrakul's Hatcher and Awakening Zone are the cheapest cards that pop those Eldrazi Spawn for us, and getting them a turn earlier than their alternatives cannot possibly be a bad thing. Mimic Vat is your best answer to removal, as it allows you to keep making token copies of, say, Emrakul's Hatcher (Great resilience after a boardwipe such as Fumigate ), or that Doom Blade d Spawnsire. Take a close look at what happen when you pair a Mimic Vat loaded with Emrakul's Hatcher, with Parallel Lives. Yes, that's fourteen tokens for three mana. And twelve of those stick!
Lastly, we've got Primal Surge , which is the only card in the whole deck that isn't a permanent. I'll let this card's effect text speak for itself.
Oh, and it's occasionally really easy to use Spawnsire's second ability, so anticipate having that option come up from time to time by either keeping some choice Eldrazi in your sideboard, or keeping a whole box of them "just in case" you have 20 mana and a Spawnsire in play. Because dropping twenty copies of
Dominator Drone
is rarely not entertaining.