Related Clues:

• No proponent
• Scarecrow, to Batman
• One to counter
• Ill-wisher
• Source of conflict
• Hatfield, to a McCoy
• Sentry's classification
• "Who goes there, friend or ___?"
• Cassius, to Caesar
• Grant, to Lee
• Them, often
• Am archaic enemy
• An archaic enemy
• Of a turn to the East, that's against you
• Enemy or competition