The effect is continuous and applies whenever something looks at the damage. If this card leaves the battlefield, damage from red and black spells will appear as its normal color. In other words, the color was not removed from the damage, the color just could not be determined while this card is in effect.
2004-10-04
wotc
It does not change the color of the source, so that things that trigger on a red spell doing damage will still trigger. The damage itself thinks it came from a colorless source, however.
2004-10-04
wotc
If the source has more than one color but at least one is red or black, then the damage is colorless and all the other colors are forgotten.
2004-10-04
wotc
Does not make red and black spells and permanents colorless. They still have color. A red spell can’t target a creature with Protection from Red due to this. The spells just act like colorless sources when dealing damage.
Format Legality
Standard
Not Legal
Future
Not Legal
Historic
Not Legal
Timeless
Not Legal
Gladiator
Not Legal
Pioneer
Not Legal
Modern
Not Legal
Legacy
Legal
Pauper
Not Legal
Vintage
Legal
Penny
Not Legal
Commander
Legal
Oathbreaker
Legal
Standardbrawl
Not Legal
Brawl
Not Legal
Alchemy
Not Legal
Paupercommander
Not Legal
Duel
Legal
Oldschool
Not Legal
Premodern
Legal
Predh
Legal
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