Base Class: Fighter
Practitioners of Zodiac Kenshido master a variety of fighting forms that allow them to channel the powers of the animals of the zodiac.
Zodiac Fighting Styles
When you choose this archetype at 3rd level, you learn to use 3 of the Zodiac Fighting Styles. You may choose any 3 from the list below. Using a bonus action, you can choose to adopt a Zodiac Fighting Style that you know, which lasts for 1 minute or until you either lose consciousness or use a bonus action to end it. You cannot use more than one style at a time, and can only activate styles a number of times equal to your constitution modifier (minimum 1). Expended uses are restored after a short or a long rest.
Boar Style
You gain the savagery of a wild boar. While using this style, if you move at least 15 feet straight toward a creature and then hit it with a melee weapon attack on the same turn, the creature must make a strength saving throw (DC = 8 + proficiency bonus + strength modifier) or be knocked prone.
Dog Style
You gain the pack mentality of a canine. While using this style, you have advantage on attack rolls against a creature if at least one of your allies is within 5 feet of the creature and the ally isn’t incapacitated.
Dragon Style
You gain the splendor of a dragon. While using this style, you have advantage on all intimidation and persuasion checks. Additionally, you can use a breath weapon once per long or short rest. This breath weapon functions the same as the feature from the dragonborn race, however, you choose which type of dragon breath you will have access to when you first begin to use this style.
Horse Style
You gain the speed and mobility of a horse. While using this style, your movement speed increases by 10 feet, and you can use a bonus action during each of your turns to take a dodge, disengage, or dash action.
Monkey Style
You gain the powerful and dexterous hands of a monkey. While using this style, when you hit a creature with a melee weapon attack, you can treat any 1 or 2 rolled on your damage dice as a 3. Additionally, any attempts to forcibly disarm you fail.
Ox Style
Your body gains the great power and strength of an ox. While using this style, you are treated as one size larger than you are for purposes of effects like grappling, being pushed, and for determining carrying capacity. Additionally, you gain a bonus to all strength checks equal to your proficiency bonus.
Rabbit Style
You gain the nimbleness and elusiveness of a rabbit. While using this style, when you are subjected to an effect that allows you to make a Dexterity saving throw to take only half damage, you instead take no damage if you succeed on the saving throw, and only half damage if you fail.
Ram Style
You gain the bashing head of a ram. While using this style, you can use one of your attacks each round to headbutt your opponent in an attempt to break a piece of their equipment. Make an unarmed melee attack against the target. If you roll a critical hit, in addition to dealing critical damage, a piece of equipment worn by the target (weapon, shield, armor, etc.) is broken, rendering it unusable for its nominal function. However, if you roll a 1, you take critical damage from the hit instead of the target, and are stunned until the end of your next turn.
Rat Style
You gain the destructive power of the incisors of a rat. While using this style, you gain advantage on melee weapon attacks against structures such as walls, doors, and floors. Additionally, when you successfully land a melee weapon attack on such a structure, you automatically deal critical damage.
Rooster Style
You gain the brash pride of the rooster. While using this style, you gain a flying speed equal to 10 feet less than your walking speed. This benefit works only in short bursts; you fall if you end your turn in the air and nothing else is holding you aloft. Additionally, as a bonus action you can make a piercing cry that awakens all creatures capable of hearing you within 100 feet of you. This cry cannot be made again until the next dawn.
Snake Style
You gain the venomous nature of a serpent. While using this style, your weapon attacks deal additional poison damage equal to half you proficiency bonus (rounded down). Additionally, if you strike a target with advantage, they must make a constitution saving throw (DC = 8 + half of your level (rounded down)) or be poisoned. A poisoned creature can repeat this saving throw on each of its turns, removing the poisoned effect on a success, and gaining immunity to being poisoned by this feature for 24 hours.
Tiger Style
You gain the ferocity of a great tiger. While using this style, whenever you hit a creature with a melee weapon attack, you can use your bonus action to make an additional melee weapon attack against that same creature.
Intermediate Training
As you progress, you gain a greater understanding of Zodiac Kenshido. At 7th level, you learn 3 additional Zodiac Fighting Styles, but you cannot choose a style you have already learned.
Advanced Training
At 10th level, you gain a more advanced level of understanding of Zodiac Kenshido. You learn 3 additional Zodiac Fighting Styles, but you cannot choose a style that you have already learned.
Expert Training
At 15th level, you have reached a level of expert of Zodiac Kenshido. You learn the final 3 additional Zodiac Fighting Styles.
Glorious Chainsaw Method
By 18th level you have fully mastered the concepts of Zodiac Kenshido, allowing you to make your weapons become like things unto chainsaws. Activating this feature requires you to expend one use of your Action Surge feature. On your turn, you can choose to use this feature before attempting to attack a creature. When activated, you can take one additional action on top of your regular action and possible bonus action on this turn. You gain advantage on all attacks you make during this turn. Additionally, during this turn your weapon attacks score a critical hit on a roll of 18-20, and you can add one additional damage die when you deal critical damage. If a creature is reduced to 0 hit points by an attack made while using this feature, it explodes.
This actually works really well for a Zodiac inspired martial artist, and a fight between an Open Hand Monk and a Kenshido Fighter would be incredible.
This is my interpretation of the fighting style used by Fighter McWarrior from the webcomic, 8-Bit Theater. While it was initially developed as a joke, feedback would be appreciated!