Duel Decks: Mirrodin Pure vs. New Phyrexia

The Duel Decks: Mirrodin Pure vs New Phyrexia was announced on February 8, 2011 and was released as a Magic Online product on January 11, 2013.

Decklist design competition
The Duel Decks announcement was also a competition where any MTG community member could send in a decklist representing a faction.

The rules were as follows:
 * You can submit up to one deck for each side.
 * Each deck must be 60 cards.
 * The Mirrodin Pure deck will be based on Platinum Angel and the New Phyrexia deck will be based on Phyrexian Plaguelord. These are the only mythic rares allowed.
 * No opposite-faction cards are allowed.
 * Each deck should have 4-8 rare cards and 20-28 land cards.
 * Include a 250-word explanation of the deck.

The winning decklists were actually submitted by Gavin Verhey, in his time before he would come to work for Wizards of the Coast.

Mirrodin Pure
 Mythic 1 Platinum Angel

Creatures 1 Ardent Recruit 1 Argent Sphinx 1 Darksteel Gargoyle 1 Darksteel Sentinel 1 Duplicant 1 Glimmerpoint Stag 1 Gold Myr 1 Grand Architect 1 Kuldotha Forgemaster 1 Lumengrid Gargoyle 1 Memnite 1 Myr Retriever 1 Silent Arbiter 1 Silver Myr 1 Spire Serpent 1 Steel Wall 1 Trinket Mage 1 Vedalken Certarch

Artifacts 1 Bonesplitter 1 Slagwurm Armor 1 Neurok Stealthsuit 1 Talisman of Progress 1 Viridian Claw 1 Thunderstaff

Enchantments 1 Arrest

Sorceries 1 Steelshaper's Gift

Instants 1 Condemn 1 Dispatch 1 Purge 1 Stoic Rebuttal 1 Test of Faith 1 Thirst for Knowledge 1 Turn the Tide 1 White Sun's Zenith

Special Lands 1 Ancient Den 1 Blinkmoth Nexus 1 Coastal Tower 1 Forbidding Watchtower 2 Seat of the Synod 2 Terramorphic Expanse

Basic Lands 8 Plains 9 Island 

Rares

 * Argent Sphinx
 * Duplicant
 * Grand Architect
 * Kuldotha Forgemaster
 * Silent Arbiter
 * White Sun's Zenith</c>
 * Blinkmoth Nexus</c>

New Phyrexia
<d title="New Phyrexia"> Mythic 1 Phyrexian Plaguelord

Creatures 1 Desecration Elemental 1 Drooling Groodion 1 Flesh-eater Imp 1 Fume Spitter 1 Mitotic Slime 1 Myr Sire 1 Necroskitter 1 Phyrexian Ghoul 1 Phyrexian Juggernaut 1 Plague Myr 1 Plaguemaw Beast 1 Protean Hulk 1 Rot Wolf 1 Soul Snuffers 1 Symbiotic Elf 1 Viridian Corrupter 2 Viridian Emissary

Enchantments 1 Diabolic Servitude

Sorceries 1 Barter in Blood 1 Black Sun's Zenith 1 Exhume 1 Innocent Blood 1 Morbid Plunder 1 One Dozen Eyes 1 Reprocess 1 Spread the Sickness 1 Triumph of the Hordes

Instants 1 Putrefy

Artifacts 1 Contagion Clasp 1 Grafted Exoskeleton 1 Mortarpod 1 Phyrexian Altar 1 Spawning Pit

Lands 10 Forest 14 Swamp 1 Tainted Wood </d>

Rares

 * Necroskitter</c>
 * Desecration Elemental</c>
 * Mitotic Slime</c>
 * Protean Hulk</c>
 * Phyrexian Altar</c>
 * Reprocess</c>
 * Black Sun's Zenith</c>