Fighter/2nd/Captain

Mettle

Starting from 2nd level, all Heart Containers you gain from this class become d12s instead of d10s—including the one you gained at 1st level.

Your heart point maximum increases by 3, and it increases by an additional 1 every time you gain a fighter level after this.

Courage

Starting from 2nd level, you have advantage on all saving throws against being charmed or frightened.

Duel

Starting from 3rd level, you can use your bonus action to compel a hostile creature within 30 feet of you to focus its aggression on you. To be affected, the target must be able to see you, and it can't already be compelled to duel another creature. A creature that can't be charmed is immune to this effect.

For 1 minute, a compelled creature target has disadvantage on attack rolls against creatures other than you. Additionally, each foot the creature moves away from you costs it 1 extra foot of movement.

If you compel another creature to duel, the previous effect immediately ends. The effect also ends if you are incapacitated.