Mark 5:9
"And he asked him, What is thy name? And he answered, saying, My name is Legion: for we are many."
Cross References (ranked by relevance)
And Jesus asked him, saying, What is thy name? And he said, Legion: because many devils were entered into him.
And they come to Jesus, and see him that was possessed with the devil, and had the legion, sitting, and clothed, and in his right mind: and they were afraid.
Thinkest thou that I cannot now pray to my Father, and he shall presently give me more than twelve legions of angels?
Then goeth he, and taketh with himself seven other spirits more wicked than himself, and they enter in and dwell there: and the last state of that man is worse than the first. Even so shall it be also unto this wicked generation.