Brannigan can enter a battle rage as a bonus action, gaining advantage on Strength checks and saves, bonus rage damage of +2 on Strength-based melee weapon attacks, and resistance to bludgeoning, piercing, and slashing damage. Rage lasts up to 1 minute, ends early if he is knocked unconscious or has not attacked or taken damage since his previous turn, and cannot be used while wearing heavy armor. He can rage 4 times per long rest.

While not wearing armor, Brannigan's AC equals 10 + his Dexterity modifier + his Constitution modifier. He can use a shield and still gain this benefit.

On his turn, Brannigan can choose to attack recklessly, gaining advantage on Strength-based melee weapon attack rolls that turn. Until his next turn, attack rolls against him have advantage.

Brannigan has advantage on Dexterity saving throws against effects he can see, such as traps and spells, unless he is blinded, deafened, or incapacitated.

Brannigan follows the Path of the Ancestral Guardian. While raging, the first creature he hits on each of his turns is marked by ancestral spirits. Until the start of his next turn, that creature has disadvantage on attacks against anyone other than Brannigan, and those other creatures have resistance to damage from the marked creature's attacks.

Brannigan increases his Strength score by 2, from 11 to 13.

Brannigan can make two attacks, instead of one, whenever he takes the Attack action on his turn.

Brannigan's speed increases by 10 feet while he is not wearing heavy armor.

While raging, Brannigan can use his reaction to reduce the damage a creature he can see within 30 feet takes from an attack by 2d6. The ancestral spirits intervene to shield the creature.

Brannigan retains the rank and standing he earned in his former army. Soldiers who recognize it may defer to him, and he can usually find a place to rest or obtain modest assistance among other military personnel.