Starting at 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.
At 13th level, you gain the ability to unerringly mimic another person's speech, writing, and behavior. You must spend at least three hours studying these three components of the person's behavior, 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.
By 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.
When you choose this archetype at 3rd level, you gain proficiency with the disguise kit and the poisoner's kit.
Starting at 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.
Starting at 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.
At 3rd level, as a bonus action, you give yourself advantage on your next attack roll on the current turn. You can use this bonus action only if you haven't moved during this turn, and after you use the bonus action, your speed is 0 until the end of the current turn.
Starting at 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.
Beginning at 7th level, you can nimbly dodge out of the way of certain area effects, such as a red dragon's fiery breath or an Ice Storm spell. When you are subjected to an effect that allows you to make a Dexterity saving throw to take only half damage, you instead take no damage if you succeed on the saving throw, and only half damage if you fail.
During your rogue 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 an area are easy marks or will provide a safe house for thieves on the run.
At 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.
At 6th level, you can choose two more of your proficiencies (in skills or with thieves' tools) to gain this benefit.
Beginning at 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 a 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.
3rd - 2d6
5th - 3d6
7th - 4d6
9th - 5d6
11th - 6d6
Your fanged maw is a natural weapon, which you can use to make unarmed strikes. If you hit with it, you deal piercing damage equal to 1d6 + your Strength modifier, instead of the bludgeoning damage normal for an unarmed strike.
As part of a short rest, you can harvest bone and hide from a slain beast, construct, dragon, monstrosity, or plant creature of size Small or larger to create one of the following items: a shield, a club, a javelin, or 1d4 darts or blowgun needles. To use this trait, you need a blade, such as a dagger, or appropriate artisan's tools, such as leatherworker's tools.
You can hold your breath for up to 15 minutes at a time.
In battle, you can throw yourself into a vicious feeding frenzy. As a bonus action, you can make a special attack with your bite. If the attack hits, it deals its normal damage, and you gain temporary hit points (minimum of 1) equal to your Constitution modifier, and you can't use this trait again until you finish a short or long rest.
Starting at 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.