Dyfed, the Guiding Hand (007) [Mystery Booster Commander Edition]

[+1]: Create two tapped Powerstone tokens. (They're artifacts with "T: Add C. This mana can't be spent to cast a nonartifact spell.")

[-X]: Untap X target artifacts.

[-6]: Search your library for an artifact card, put it onto the battlefield, then shuffle.

Dyfed, the Guiding Hand can be your commander.