{Akroma's Memorial} what does the protection part mean? I had been told that it means that even you can not cast red or black???
No. It means that your creatures cannot be targeted by black and red spells or abilities from current color sources, damage from black and red sources are prevented and ur creatures cannot be blocked by black and red creatures...;)
Protection is an attribute that means a card cannot be dealt damage, enchanted, blocked, or targeted by a source that it is protected from. In this case, your creatures are protected from those 4 things (remember the acronym "DEBT" to remember them!) from any red or black sources.
You are still allowed to cast red and black spells with {Akroma's Memorial} on the battlefield, as long as those spells are a legal target. If your opponent has the memorial, you can't cast {lightning bolt} on his creatures, but you CAN still cast it on the player, for example. You can't cast {Doom Blade} on his creature because doom blade cannot target it, but you can still cast {mutilate}, because it doesn't target anything.
Make sure to check out the Q&A and FAQ sticky above! And the basic rulebook is linked at the bottom of it too, which is worth reading!
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