Building a colorless EDH deck can be a major challenge given that colorless doesn't have the same arrangement of spells that the main 5 colors of the MTG color pie have access to. However, that is not to say that colorless decks can't be interesting and varied in their approach to the game. I use my current Karn, Silver Golem build to explain some of the challenges that I faced building the deck as well as the freedom I had to make the deck my own just using artifacts I had lying around in my collection. Karn is a very versatile Commander and can go in a number of different ways.
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