Defender <i>(This creature can't attack.)</i>
Whenever Wall of Caltrops blocks a creature, if at least one other Wall creature is blocking that creature and no non-Wall creatures are blocking that creature, Wall of Caltrops gains banding until end of turn. <i>(If any creatures with banding you control are blocking a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by.)</i>