| arguer |
| brawler |
| contender(noun, contestant) |
| aristarch(noun, opponent, enemy, attacker, critic) |
| attacker(noun, opponent, enemy, critic, defamer) |
| backseat driver(noun, expression, opponent, enemy, attacker) |
| belittler(noun, opponent, enemy, attacker, critic) |
| bickerer |
| blamer(noun, opponent, enemy, attacker, critic) |
| carper(noun, opponent, enemy, attacker, critic) |
| caviler(noun, opponent, enemy, attacker, critic) |
| censor(noun, opponent, enemy, attacker, critic) |
| censurer(noun, opponent, enemy, attacker, critic) |
| challenger(noun, contestant) |
| complainant(noun, opponent, enemy, attacker, critic) |
| complainer(noun, opponent, enemy, attacker, critic) |
| contester |
| critic(noun, opponent, enemy, attacker, censor) |
| debater |
| defamer(noun, opponent, enemy, attacker, critic) |