Wandering Ronin

Ronin literally means "wave man". It is an idiomatic expression for "vagrant" or "wandering man", someone who finds the way without belonging to one place. Ronin were depicted as the shadows of samurai, master-less and less honorable. Not having the status or power of employed Samurai, Ronin were often disreputable and festive, and the group was often a target of humiliation or stigma. It was undesirable to be a Ronin, as it meant being without a rank or means. Ronin find their way through life as mercenaries or loners. They hone their skills for survival by any means necessary and victory at any cost. Some come from the ranks of disgraced families or impoverished farms. Other Ronin may have found themselves on the path of the wanderer due to treachery or just plain bad luck. Regardless of how they set foot on the path, they are now caught in a struggle to survive outside of noble doctrine.

Bonus Proficiency

When you choose this archetype at 3rd level, you gain proficiency in one of the following skills of your choice: Deception, Persuasion, Sleight of Hand, or Stealth. Alternatively, you learn one language of your choice.

Vicious Strike

Starting at 3rd level, your brutality in battle can be focused into a staggering blow. As a bonus action on your turn, you can add 2d6 to an attack until the end of the current turn. An opponent injured by this attack has disadvantage on melee attacks against you until the start of your next turn. The number of damage die increases when you reach certain levels in this class, increasing by 1d6 at 10th level and at 15th level.
You can use this feature three times, and you regain all expended uses of it when you finish a long rest.

Elusive Wanderer

Starting at 7th level, your sense of self preservation has been honed like a knife in social settings. Whenever you make a Charisma (Deception) check, you gain a bonus to the check equal to your Intelligence modifier.

Your self preservation also causes you to gain proficiency in Intelligence saving throws. If you already have this proficiency, you instead gain proficiency in Wisdom or Charisma saving throws (your choice).

Brutal Combatant

Starting at 10th level, when you roll initiative and have no uses of Vicious Strike remaining, you regain one use.

Vicious Onslaught

Starting at 15th level, you may Dash as a bonus action. When you do so you may choose to  spend a use of Vicious Strike on one target within 5 feet of you during this movement. This attack has advantage if you move more than 10 feet before striking. 

Enduring Survivalist

Starting at 18th level you gain the ability to survive regardless of the odds. Whenever you would fail a saving throw that would result in death you may as a reaction expend a use of your Indomitable trait  to automatically succeed and gain 10 temporary hit points.