Shadow

Shadow is a keyword ability on creatures that serves as both an evasion ability and a blocking restriction. An attacking creature with shadow can only be blocked by a defending creature with shadow, and a defending creature with shadow can only block an attacking creature with shadow. It was first seen in the Tempest block, and was revisited in the Time Spiral block. Shadow is found on black, white or blue creatures, while a few red and green walls are able to block shadow creatures.

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