You focus your training on the grim art of death. Rogues who adhere to this archetype are diverse: hired killers, spies, bounty hunters, and even specially anointed priests trained to exterminate the enemies of their deity. Stealth, poison, and disguise help you eliminate your foes with deadly efficiency.

Infiltrator

3rd-level Assassin feature

You gain proficiency with two of the following tools of your choice: a disguise kit, a forgery kit, or a poisoner's kit. The gold and time you must spend to craft disguises, forge documents, or brew poisons with the chosen tools is halved.

In addition, you can add your Intelligence modifier to any Charisma ability checks you make with those tools, as well as to any Charisma (Deception) or Charisma (Performance) checks you make to pass yourself off as a different person.

Assassinate

3rd-level Assassin feature

You use your knowledge and wits to strike at the most opportune moment. You gain a bonus to your initiative rolls equal to your Intelligence modifier.

In addition, when you hit a creature with an attack, and you have advantage on the attack roll, you can turn that hit into a critical hit. You can use this ability a number of times equal to your proficiency bonus, and regain all expended uses when you finish a long rest.

Evanescence

9th-level Assassin feature

You are an expert at removing yourself from suspicion and danger. You have advantage on ability checks you make to obscure your influence, such as creating false evidence or making an object appear untouched after interacting with it.

In addition, when you kill a creature or reduce it to 0 hit points, you can use your reaction to take the Dash, Disengage, or Hide action.

First Strike

13th-level Assassin feature

You are at your deadliest when you get the drop on your enemies. You have advantage on attack rolls against any creature that hasn’t taken a turn in the combat yet.

In addition, when you hit a creature that is surprised with an attack, you can deal extra damage to it equal to half the number of Sneak Attack dice for your level (rounded down).

Death Blow

17th-level Assassin feature

You become a master of instant death. Once per turn, when you hit a creature with an attack, you can force it to make a Constitution saving throw (DC 8 + your Dexterity modifier + your proficiency bonus). On a failed save, the target becomes vulnerable to all of the attack’s damage. If the creature has resistance or immunity to one of the attack's damage types, it loses that resistance or immunity for the attack, and the damage it takes of that type isn't doubled. Any damage the creature takes that it would normally be immune to is also halved.

On a successful save, the target takes the attack's normal damage, and can't be affected by this feature for the next 24 hours.