they use their skills to gather information for lords, or to assassinate enemies. Ninjas are skillful and quick with there work, and never go off of a plan or flee from a fight. 

Ninja Training

When you choose this tradition at 3rd level, you gain proficiency with the disguise kit and poisoner’s kit.  You also gain proficiency in the Stealth skill.  If you are already proficient in Stealth, your proficiency bonus is doubled.

Martial spellcasting

When you reach 3rd level you can choose one 1st level wizard spell of your choice to be able to cast once per long rest. at 6th level you also learn an additional second level spell at 11th one additional 3rd level spell and at 17th one additional 4th level spell.   

Sneak Attack

Beginning at 3rd level, you know how to strike subtly and exploit a foe’s distraction. Once per turn, you can deal an extra 1d4 damage to one creature you hit with an attack if you have advantage on the attack roll. The attack must use your martial arts, a ranged weapon, or a monk weapon.

You don’t need advantage on the attack roll if another enemy of the target is within 5 feet of it, that enemy isn’t incapacitated, and you don’t have disadvantage on the attack roll.

The amount of the extra damage increases as you gain levels in this class, as shown in the Martial Arts column of the Monk table.

Assassination

Beginning at 6th Level, your sneak attacks now deal an extra damage equal to double the amount shown on the Martial Arts column of the Monk table.  Additionally, you may spend up to two ki points to increase the sneak attack damage further.  Each ki point spent allows you to roll one additional die of the type shown on the Martial Arts column of the Monk table.

Shadow Strike

Beginning at 11th level, you have mastered the art of striking from the shadow.  Any hit on a surprised foe is automatically a critical hit.  If you roll a natural critical hit, the damage is doubled.

Quivering Palm

At 17th level, you gain the ability to set up lethal vibrations in someone’s body. When you hit a creature with an unarmed strike, you can spend 3 ki points to start these imperceptible vibrations, which last for a number of days equal to your monk level. The vibrations are harmless unless you use your action to end them. To do so, you and the target must be on the same plane of existence. When you use this action, the creature must make a Constitution saving throw. If it fails, it is reduced to 0 hit points. If it succeeds, it takes 10d10 necrotic damage.

You can have only one creature under the effect of this feature at a time. You can choose to end the vibrations harmlessly without using an action.