Possible Clues:

• Not invincible
• Serve as a piece of furniture, somehow not the best?
• Able to be defeated
• Act as a board can be defeated?
• Happen to lead a board that is not invincible
• Attend island uprising which can be crushed
• Have four legs and flat top? That's not necessarily best
• A drum is so round and strong
• What poor teams are best qualified to provide?
• Open to being defeated