Corsair

Many people have called themselves corsairs. Anybody who sails along the seas can call themselves as such. Pirates and Navy alike, from the lowest of thieves to the most fearsome buccaneers, and from the freshly recruited seamen to the admiralty ranks of the Navy, all are corsairs in their own right. Among these, however, there are a select few who have truly mastered the art of naval combat, and are worthy of renown while patrolling the open waters. Those who follow the colloquially-named "corsair" martial archetype, are a true terror to behold, who can battle in any foreseeable situation.

Nautical Expertise

Beginning at 3rd level, you know your way around the seven seas, and your combat skills are fine tuned to nautical encounters. You gain proficiency in Firearms. You also ignore the loading property of ranged weapons you use, you can make a ranged attack at a target within 5 feet of you without rolling at disadvantage, and while you are wielding a melee weapon with only one hand, you can make a Parry reaction. You can use your reaction to impose disadvantage on a melee attack made against you.

Additionally, you gain proficiency in Cartographer's Tools, Navigator's Tools, and Water Vehicles if you don't already have these proficiencies.

Finally, you gain the Mariner Fighting Style. If you already have this Fighting Style, you instead choose to gain either the Archery Fighting Style or the Dueling Fighting Style.

Mariner - As long as you are not wearing heavy armor or using a shield, you have a swimming speed and a climbing speed equal to your normal speed, and you gain a +1 bonus to AC.

Maritime Combatant

Knowledgeable in the art of combat on the open seas, starting at 7th level, you gain the following techniques:

Sniper - Attacking a target using the long range of a ranged weapon does not impose disadvantage on the attack roll. You deal an additional 2 damage with each ranged attack that you make.

Musketeer - Your Parry reaction now also provides you with a bonus to your AC equal to your Dexterity modifier until the start of your next turn. Whenever you attack a target using a melee weapon you wield in one hand, you can move away from that target without provoking opportunity attacks against it, regardless of whether or not the attack hit.

Mariner's Prowess

Well versed in techniques of swords and bullets, starting at 10th level, you gain the following techniques:

Grape Shot - As an action, you can expend one piece of ammunition, and make a special attack. If you are using a firearm, you fire off a barrel packed with nails and shards of glass, going out in a 30 foot cone from you. If you are using a ranged weapon that is not a firearm, you fire off a modified piece of ammunition, going out in a 60 foot line from you. Targets within this range must make a Dexterity saving throw, save DC equal to 8 + your weapon's attack modifiers. On a failed save, the targets take piercing damage equal to the weapon's standard damage roll + any modifiers that are added + an additional roll of the weapon's damage die. On a successful save, the targets take half as much damage. If the weapon or ammunition was magical, this damage is considered magical for the purposes of overcoming resistances and immunities against nonmagical damage.

Riposte - After you use your Parry reaction, and the attack roll either misses or hits, you can use the same reaction to make an attack roll against the target that attacked you, then you can move up to half your speed away from the target, without provoking opportunity attacks. Your walking speed also increases by 10 feet.

Martial Stance

Always prepared to go toe-to-toe with an enemy or more, starting at 15th level, you gain the following techniques:

Aiming Stance - You can use your bonus action before your action if you are wielding a ranged weapon, to steady your senses. Ranged attack rolls you make during the turn you use this feature are made at advantage. Once you use this feature, you can't use it again until the turn after you don't use your bonus action.

Parrying Stance - You can take the Dodge action as a bonus action. You must have a melee weapon in only one hand in order to benefit from this feature. If you take the Dodge action, for the duration, allies within 10 feet of you also gain the benefits of the Dodge action.

Recovering Stance - Whenever you use your bonus action to use your Second Wind feature, you gain a bonus of 5 to your saving throws and AC until the end of your next turn, and you gain temporary hit points equal to your fighter level.

True Captain

You are unmistakably, the one who is truly in charge of any vessel you happen to be on. Beginning at 18th level, whenever you use your Action Surge, you gain the following benefits:

• If you target only one target for attack rolls you make during this turn, you have advantage on all of those attack rolls, and you only expend one piece of ammunition (if any). If you already have advantage on attack rolls against the target, you gain a bonus to attack rolls and damage rolls against the target, equal to half your proficiency bonus.
• If you target more than one target for attack rolls you make during this turn, you can make an additional two attack rolls. You must target only one target with each attack roll you make this turn.