Rule 815.1.c.2
If more than one unit with Tank is present with the same controller in Combat, damage may be assigned to any of them. Units without Tank are invalid assignments until all units with Tank have lethal damage assigned to them.
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If more than one unit with Tank is present with the same controller in Combat, damage may be assigned to any of them. Units without Tank are invalid assignments until all units with Tank have lethal damage assigned to them.