Assassin

One of the Rogue classes.

Hit Points
Hit Dice: 1d8 per level

Hit Points at 1st Level: 8 + CON modifier

Hit Points at Higher Levels: 1d8 + CON modifier per level after 1st

Proficiencies
Armour: Light armour

Weapons: Simple weapons, hand crossbows, longswords, rapiers, shortswords

Tools: Thieves' tools

Saving Throws: Dexterity, Intelligence

Skills: Choose four from Acrobatics, Athletics, Deception, Insight, Intimidation, Investigation, Perception, Performance, Persuasion, Sleight of Hand, and Stealth

Equipment
You start your adventure with the following equipment, in addition to the equipment granted by your background:
 * (a) a rapier, or (b) a shortsword
 * (a) a shortbow and quiver of 20 arrows, or (b) a shortsword
 * (a) a burglar's pack, (b) a dungeoneer's pack, or (c) an explorer's pack
 * Leather armour, two daggers, and thieves' tools

Features & Abilities

 * Thieves' Cant (all levels). During your training you learned thieves' cant, a secret mix of dialect, jargon, and code that allows you to hide messages in seemingly normal conversation. Only another creature that knows thieves' cant understands such messages. It takes four times longer to convey such a message than it does to speak the same idea plainly. In addition, you understand a set of secret signs and symbols used to convey short, simple messages, such as whether an area is dangerous or the territory of a thieves' guild, whether loot is nearby, or whether the people in the area are easy marks or will provide a safe house for thieves on the run.
 * Expertise (1st level). Choose two of your skill proficiencies, or one of your skill proficiencies and your proficiency with thieves' tools. Your proficiency bonus is doubled for any ability check you make that uses either of the chosen proficiencies.
 * Sneak Attack (1st level). You know how to strike subtly and exploit a foe's distraction. Once per turn, you can deal an extra 1d6 damage to one creature you hit with an attack if you have advantage on the attack roll. The attack must use a finesse or ranged 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 (see table below).
 * Cunning Action (2nd level). Your quick thinking and agility allow you to move and act quickly. You can take a bonus action on each of your turns in combat. This action can be used only to take the Dash, Disengage, or Hide action.
 * Assassin's Proficiencies (3rd level). You gain proficiency with the disguise kit and poisoner's kit.
 * Assassinate (3rd level). 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, any hit you score against a creature that is surprised is a critical hit.
 * Ability Score Improvement (4th level). You can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can’t increase an ability score above 20 using this feature.
 * Uncanny Dodge (5th level). When an attacker that you can see hits you with an attack, you can use your reaction to halve the attack's damage against you.
 * Greater Expertise (6th level). Choose two more of your skill proficiencies, or one of your skill proficiencies and your proficiency with thieves' tools. Your proficiency bonus is doubled for any ability check you make that uses either of the chosen proficiencies.
 * Evasion (7th level). You can nimbly dodge out of the way of certain area effects, such as a red dragon's fiery breath of an ice storm spell. When you are subjected to an effect that allows you to make a Dexterity saving throw to only take half damage, you instead take no damage if you succeed on the saving throw, and only half damage if you fail.


 * Ability Score Improvement (8th level). You can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can’t increase an ability score above 20 using this feature.


 * Infiltration Expertise (9th level). You can unfailingly create false identities for yourself. You must spend seven days and 25 gp to establish the history, profession, and affiliations for an identity. You can't establish an identity that belongs to someone else. For example, you might acquire appropriate clothing, letters of introduction, and official-looking certification to establish yourself as a member of a trading house from a remote city so you can insinuate yourself into the company of other wealthy merchants. Thereafter, if you adopt the new identity as a disguise, other creatures believe you to be that person until given an obvious reason not to.
 * Ability Score Improvement (10th level). You can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can’t increase an ability score above 20 using this feature.
 * Reliable Talent (11th level). You have refined your chosen skills until they approach perfection. Whenever you make an ability check that lets you add your proficiency bonus, you can treat a d20 roll of 9 or lower as a 10.


 * Ability Score Improvement (12th level). You can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can’t increase an ability score above 20 using this feature.
 * Imposter (13th level). You gain the ability to unerringly mimic another person's speech, writing, and behaviour. You must spend at least three hours studying these three components of the person's behaviour, listening to speech, examining handwriting, and observing mannerisms. Your ruse is indiscernible to the casual observer. If a wary creature suspects something is amiss, you have advantage on any Charisma (Deception) check you make to avoid detection.
 * Blindsense (14th level). If you are able to hear, you are aware of the location of any hidden or invisible creature within 10 feet of you.
 * Slippery Mind (15th level). You have acquired greater mental strength. You gain proficiency in Wisdom saving throws.


 * Ability Score Improvement (16th level). You can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can’t increase an ability score above 20 using this feature.
 * Death Strike (17th level). You become a master of instant death. When you attack and hit a creature that is surprised, it must make a Constitution saving throw (DC 8+ DEX modifier + proficiency bonus). On a failed save, double the damage of your attack against the creature.
 * Elusive (18th level). You are so evasive that attackers rarely gain the upper hand against you. No attack roll has advantage against you while you aren't incapacitated.


 * Ability Score Improvement (19th level). You can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can’t increase an ability score above 20 using this feature.
 * Stroke of Luck (20th level). You have an uncanny knack for succeeding when you need to. If your attack misses a target within range, you can turn the miss into a hit. Alternatively, if you fail an ability check, you can treat the d20 roll as a 20. Once you use this feature, you can't use it again until you finish a short or long rest.

Meta Notes
Vanilla Rogue with Assassin subclass