Certain Battle for Zendikar Eldrazi cards have:
Devoid (This card has no color.)
According to a video by Mark Rosewater, that means regardless of the colored mana required to cast the card, the card itself is colorless.
So then, just like the example with Extort: even though there are color mana symbols in the reminder text, those do not count towards color identity.
Given this, if I have a colorless Commander (e.g. Kozilek, the Great Distortion, Ulamog, the Ceaseless Hunger, Karn, Silver Golem, etc.), can I include Devoid cards - as they are colorless? I checked various sources and seem to come up with equal support pro and con. The last line of 105.2 reads:
An object’s color or colors may also be defined by a color indicator or a characteristic-defining ability.
Devoid is such a defining ability...