Brother Against Brother is a popular set of rules for miniature wargaming, recreating small skirmishes primarily of the American Civil War, as well as the French and Indian War and similar time periods.
The rules are for company-level fights, with each player commanding at least a squadron or similar small group of 9-10 soldiers.
Each miniature figure represents 1 combatant within the squad, led by a Sergeant or similar non-commissioned officer.
Taking casualties or charging requires a group to draw one of 19 Morale Cards, often causing 'skeedaddling' (stragglers), out of ammunition conditions, or other consequences.
Optional rules cover troop quality, special event cards, types of fire, and allow leaders to be "personalized."