Before New Phyrexia, there was Mirrodin. A world of perfect metal created by Karn, the silver golem. This episode goes back to the origins of this fascinating plane — and to the seeds of the corruption that would destroy it.
The Birth of a World

Karn, after acquiring Urza's planeswalker spark, decided to create a perfect world — a sanctuary of metal where organic corruption would not exist.
He named this world Argentum, and filled it with metallic creatures of his own creation. But perfection is impossible to maintain, and Karn made a fatal mistake: he left a part of himself — contaminated by Phyrexian oil — in the heart of his world.
The Mycosynth

The mycosynth — the living metal that formed the foundation of all life on Argentum — began to evolve in unexpected ways. The metal creatures developed minds of their own. Some even forgot they had been created.
Karn, absorbed by other concerns across the Multiverse, did not realize that his perfect world was slowly being corrupted from within.
Sources
- MTG Wiki: Mirrodin
- Mirrodin (Magic expansion, 2003)
- Darksteel (Magic expansion, 2004)

