Devoid is a characteristic defining ability that can appear on any card type, and simply makes the card colorless regardless of its mana cost. And that’s entirely it.
There’s a couple of notes, but they’re pretty quick;
- A card with devoid can be granted a color by another effect, in which case it will be the granted color but still technically have the mechanic.
- As a characteristic defining ability, the card is colorless in all zones.
- In a weird quirk of the way layers work, even if a devoid card loses the ability, it will still be colorless. Effects that determine color apply in a higher layer than the card losing devoid would be considered, it’s a whole thing.
And that’s it. Devoid was not terribly popular, as it seemed like an odd choice to devote a full set mechanic slot to. For what it’s worth, Mark Rosewater (head designer for Magic) agrees in hindsight, stating that it should have just been an unnamed mechanic that appeared as rules text on cards, or even changed to a supertype. Don’t expect to see it pop up again in its current form, but there are several notable cards with the ability, which often ends up affecting the game in surprising ways.
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