Scars of Mirrodin

"The Corrosion Begins": The metal plane of Mirrodin shines under the light of five suns ... but it's now tarnished by the deadly scourge known as Phyrexia. Besides the Mirran-Phyrexian conflict, the story also revolves around several planeswalkers: Elspeth Tirel returns while a new planeswalker by the name of Koth is introduced, a Vulshok native to Mirrodin. Venser and Tezzeret are also involved in the storyline.