Seafarer

The seafarer has gone by many a name, depending on the nature of their time upon the sea. Mariner, bluejacket, sea dog -- all of these heart sailors are tied together by a life on the waters and the trials it puts one through. The seafarer is not always the most practiced fighter, but what they lack in expertise they make up for in camaraderie. A sailor knows how to bond with their fellow crew to finished a task, and their shanty songs keep morale high through even the roughest battle.

Sailor's Life

When you choose this archetype at 3rd level, you gain proficient with water vehicles and navigators tools. In addition, you have a swimming speed equal to your walking speed and you can hold your breath for twice as long as normal.

Sea Shanties

Starting at 3rd level, you can sing sea shanties to spur your allies into rhythmic cooperation. As a bonus action, you can start a shanty which lasts for 1 minute, or until you concentration is broken (as if concentrating on a spell) your you stop singing (no action required). When you do, and at the start of each of your turns while you are singing, each friendly creature within 30 feet of you that can hear you can use its reaction to join in. A creature that joins your shanty, whether by singing, drumming an accompanying beat, or moving in step with the rhythm, gains the benefits of the shanty until the start of your next turn. 

Whenever you start a shanty, you choose which of the following songs to sing.

Dead Man's Folly A song of avoiding trouble and following orders. Each creature participating in this shanty has advantage on Strength saving throws and a +1 bonus to attack rolls against a target if a friendly creature that isn't incapacity is within 5 feet of the target.

Roll the Tide Along. A song of moving forward under any circumstances. Each creature participating in this shanty has advantage on Dexterity saving throws and cannot be knocked prone or pushed against its will.

Drunken Sailor's Morning. A song of enduring pain and consequences. Each creature participating in this shanty has advantage on Constitution saving throws and gains temporary hit points equal to your fighter level each time it joins the shanty.

Forget Not Your Mates. A song of recalling past friends and experiences. Each creature participating in this shanty has advantage on Intelligence saving throws and reduces the damage it takes from spells by an amount equal to your proficiency bonus.

Blood Red Sirens. A song of working through oncoming terrors. Each creature participating in this shanty has advantage on Wisdom saving throws and is immune to the charmed and frightened condition while participating.

Haul, Ye Wayfarers. A song of camaraderieship and shared labor. Each creature participating in this shanty has advantage on Charisma saving throws and a +1 bonus to AC if it is within 5 feat of another friendly creature that isn't incapacitated.

Once you use this feature to sing a shanty, you can't use it again until you finish a short or long rest. You can use this feature twice between short and long rests starting at 15th level.

Sound of the Sea

Starting at 7th level, you can add half your proficiency bonus (round up) to any Strength, Dexterity, or Constitution check you make that doesn’t already use your proficiency bonus.

In addition, when you make a running long jump, the distance you can cover increases by a number of feet equal to your Strength modifier.

Working Song

At 10th level, when a creature, including yourself, is participating in your sea shanty, it can add a bonus equal to your Charisma modifier (minimum +1) to an attack roll, damage roll, or saving throw it makes. Once it add this bonus to a roll, it cannot do so again until the start of its next turn.

Archery

You gain a +2 bonus to attack rolls you make with ranged weapons.

Defense

While you are wearing armor, you gain a +1 bonus to AC.

Dueling

When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.

Great Weapon Fighting

When you roll a 1 or 2 on a damage die for an attack you make with a melee weapon that you are wielding with two hands, you can reroll the die and must use the new roll, even if the new roll is a 1 or a 2. The weapon must have the two-handed or versatile property for you to gain this benefit.

Protection

When a creature you can see attacks a target other than you that is within 5 feet of you, you can use your reaction to impose disadvantage on the attack roll. You must be wielding a shield.

Two-Weapon Fighting

When you engage in two-weapon fighting, you can add your ability modifier to the damage of the second attack.

Deep Lungs

Starting at 15th level, the range of your Sea Shanties increases to 60 feet. In addition, you can hold your breath for a number hour equal to your Constitution modifier (minimum1). 

Anchoring Bonds

Starting at 18th level, you can use a bonus action while concentrating on a sea shanty to allow each creature participating in your sea shanty to make one melee weapon attack against a creature within range or move up to half its speed (NO ACTION required by the participant).
You can use this feature a number of times equal to your proficiency bonus, and regain all expended uses when you finish a long rest.