Guul Draz Vampire
Creature — Vampire Rogue
As long as an opponent has 10 or less life, this creature gets +2/+1 and has intimidate. (It can't be blocked except by artifact creatures and/or creatures that share a color with it.)
"A creature's bloodscent is a beacon that cannot be disguised."
Steve Argyle
Zendikar (ZEN)
• #93Rulings
If an attacking creature has intimidate, what colors it is matters only as the defending player declares blockers. Once it’s blocked, changing its colors won’t change that.
(wotc • 2009-10-01)
Intimidate looks at the current colors of a creature that has it. Normally, if Guul Draz Vampire has intimidate, it can’t be blocked except by artifact creatures and/or black creatures. If it’s turned white, then it can’t be blocked except by artifact creatures and/or white creatures.
(wotc • 2009-10-01)
Rulings
If an attacking creature has intimidate, what colors it is matters only as the defending player declares blockers. Once it’s blocked, changing its colors won’t change that.
(wotc • 2009-10-01)
Intimidate looks at the current colors of a creature that has it. Normally, if Guul Draz Vampire has intimidate, it can’t be blocked except by artifact creatures and/or black creatures. If it’s turned white, then it can’t be blocked except by artifact creatures and/or white creatures.
(wotc • 2009-10-01)