Ninja

This subclass gives many benefits that allow the character to use poison and bleeding to cause the opponent to fall with only one attack, or to use hit and run tactics, relying on stealth to make it so that they rarely take damage.

knowledge of the human body

Due to your knowledge of the human body, you can cause a target to start bleeding when you land a sneak attack. At the start of each of their turns, the target must make a CON save to stop bleeding or take 1d4 damage. This damage increases at 5th level (1d6), 11th level (1d8), and 17th level (1d10).

Skills of a professional

you gain expertise or proficiency on one of the following tools or skills; thieves tools, stealth, acrobatics, deception, animal handling, or nature.

Master of movement

You gain 10 extra feet of movement, and your speed is not decreased by climbing or moving on rough terrain

knowledge of concoctions

you gain proficiency with the poisoner’s kit and medicine checks, and you add your expertise bonus to the dc of the poison or the healing of potions that you use. You have advantage on saves against poison, and you resist poison damage.

Master of the night

you gain advantage on stealth rolls and do not gain disadvantage on perception while in dim light