Domain Zoo is a fast aggro-tempo deck that applies early pressure with Ragavan and Territorial Kavu, backed by Leyline of the Guildpact to power up Scion of Draco, and Leyline Binding plus Consign to Memory for disruption. Trinisphere is the centerpiece of the sideboard plan here—it forces Ragavan, Lightning Bolt, and Stubborn Denial all to cost at minimum three mana, dramatically slowing their early game and buying the time needed to deploy game-ending Eldrazi. Unholy Heat provides efficient answers to Ragavan (which steals your cards with haste) and Phelia before they accumulate value, and achieves delirium easily given the density of artifacts and lands in the deck. Fade from History, a sorcery, cleanly answers their enchantment package—Leyline of the Guildpact and Leyline Binding—that would otherwise enable Scion of Draco's bonus abilities and strand your threats. Ugin, Eye of the Storms and Sire of Seven Deaths come out as the highest-CMC, lowest-impact cards versus a deck that can close quickly, while two Kozilek's Returns in the remaining sixty are sufficient to clear small creatures when cast from the graveyard off a large Eldrazi.