This is an Eldrazi midrange deck that takes a different approach using mono-red. Usually, mono-red Eldrazi decks use a lot of thopter-generating cards to take advantage of Vile Aggregate, but this one takes a more pure beatdown approach, with lots of individually important midrange attackers and only a little bit of thopter stuff.
Time to go a bit more in-depth. Basically, this deck has two ways of winning. Either out-combat the opponent with cards like Vile Aggregate, Reality Smasher and Endless One (preferably enhanced by Ruins of Oran-Rief) until you can swing through for lethal, or build up enough power on board to kill them in a few turns with some Barrage Tyrant flings. Helping this plan along the way are cards like Spatial Contortion and Devour in Flames.
Going card-by-card:
Spatial Contortion: Nine times out of ten, will be used as early-game removal. Has the potential to buff a Vile Aggregate or Reality Smasher for extra reach, which combos neatly with Barrage Tyrant.
Hedron Crawler: A nice little bit of ramp. Most relevant when it comes to getting Thought-Knot Seer out before a Collected Company can drop.
Matter Reshaper: A nice early-game blocker and attacker, and nabs you a card when it dies. Cool stuff. Good card.
Vile Aggregate: One of the reasons for choosing the red variant. Although this deck focuses less on the Thopter generators, Aggregate can still get to respectable levels in this deck, and is a daunting blocker against aggressive decks even with small Power.
Pia and Kiran Nalaar: Cool synergy with Vile Aggregate, and a real obstacle in the way of aggro decks.
Thought-Knot Seer: Speaks for itself.
Reality Smasher: The star of the show. One of my favorite cards in Standard at the moment, good against any deck that I want to swing into (all of them). Core part of the "winning combat" plan.
Barrage Tyrant: A sort of alternate win condition that skips combat altogether to take off big chunks of the opponent's life, 5 or 6 at a time. One in the mainboard as a wild card and two more in the sideboard for matchups in which the fling strategy is more viable, like midrange or ramp.
Devour to Flames: Very, very important. The versatility provided by this card lets it keep up an assault, get you better cards, and give you a board-wipe against white aggressive decks when they start getting big.
Ruins of Oran-Rief: Coming in tapped is a pain, but buffing everything by that crucial 1 P/T is frequently relevant, and in multiples can be nutso.
Foundry of the Consuls: Better against some decks than others, but a colorless source that gives you some Thopters is a good thing.
Sideboard:
Barrage Tyrant: Explained above.
Consuming Sinkhole: Experimental. I really, really hate shambling vents.
Eldrazi Obligator: Comes in against big ramp decks, midrange decks, or control decks that have trouble with a 3 power 3-drop with haste.
Endbringer: A big, dangerous threat to come in against slower decks. Dominates games by itself.