If a player is playing with black and I have a creature that has "Protection from Black" can he block me??? Can he kill me with Terror??? Can he enchant this creature with anything black??? Can he use any black spell or ability to -X/-X to this creature??? What can he do to kill this creature using unly black???
Protection from a color or artifact has 3 sub groups 1- all damage done by color is reduced to zero ie if you block a 4/4 green creature with a 2/2 PFG creature the 4 damage done to your creature is reduce to zero. If the green creature has trample he has to lethal damage, in this case 2, to the creature and the remainder(2) assigned to the player. The Green creatures controller could assign 2,3 or 4 points of damage to the FPG creature. 2-Protection from color or artifact cannot be blocked by that color or artifacts. 3-Creatures with protection cannot be target of spells or effects of the protected color. Global spells do not target specific creature. A Nightwing Glider cannot be terrored but a bog elemental can be wave of reckoning'd. The black player could save his creature if he had a Distorting lens and turned the Bog elemental white. 4- Remove creature enchantments of the protected color
Responding specifically to your questions... His black creatures can't block your creature. Terror can't target your creature. No black enchantments can target or otherwise be moved onto your creature. Yes. Any black spell which does not specifically target your creature, or deal damage to it, will be effective. Massacre would be one example; Engineered Plague would be another.
What if I have a Circle of Protection: White and my oponent casts a Disenchant against it, can I give protection to the circle against the Disenchant???
Story Circle, and any Cicle or Rune of Protection only protects it's caster; not the creatures, not the permenants, nothing, just the caster. Terror can't destory any black creatures, wheather that creature has protection from black or doesn't, Terror can't target black creatures. As a matter of fact, most black creature removal can't target black creatures.
Strictly speaking, it's not the caster that the various circles, runes, and thingies protect; it's the controller. You can Steal Enchantments, ya know. *grumble*
He might be able to use Diabolic Edict to remove your pro-black creature, if it's the only one you control (or he gets rid of all your others by other means).
a creature wit Protection from has protection fron D-E-B-T D: Damage E: Enchantments B: Blocking T: Targeting Like spidey said there are other means of getting of a pro creature.