Shadow Assassin

Shadow Assassins are a coveted class of rogues by races such as the Drow, Duergar, and dwarves who live in the shadows and darkness. They lurk unseen in the darkened corners or alleyways and war rooms alike, watching and waiting for the most opportune moment to strike before disappearing back into the darkness like the phantoms they are.

Assassinate

Starting at 3rd level, you are your deadliest when you get the drop on your targets. You have advantage on attack rolls made against any creature that hasn’t taken a turn in the combat yet. Additionally any hit you land against a creature that is surprised is automatically a crit.

Always prepared

When you choose this archetype at 3rd level you also gain the ability to, as a bonus action, create an object of hardened shadow. This construct can take the form of your thieves tools, or a dagger. Objects created with this feature fade back to shadow when they leave the hands of the shadow assassin.

Shadow Step

Starting at 6th level, you gain the ability to step through the darkness effortlessly as though you were the darkness itself. As a bonus action, you can teleport 60 feet to an unoccupied spot you can see, as long as both you and the target location are in dim light or darkness. Until the end of your turn you have advantage on the next melee attack you make.

This ability replaces the standard 6th level feature of gaining expertise in two existing proficiencies.

Cloak of Shadows

Starting at 9th level, you have learned to bend shadows around you. You can use your action to become invisible for up to one minute or until you make an attack, cast a spell or are in an area of bright light. 

Aspect of Shade

You have learned to call upon the darkness itself to empower your attacks. Starting at 13th level, as a free action you can imbue your melee and ranged weapon attacks with necrotic energy until the beginning of your next turn or you end your turn in normal or bright light. For the duration, this adds 1d10 necrotic damage to damage rolls and the attack counts as magical for the purposes of overcoming resistances. You may use this feature a number of times equal to your proficiency  modifier and regain expended uses of this feature after a long rest. At 17th level the damage increases to 2d10 necrotic damage.

Aura of Shadows

Starting at 17th level, your body and soul have become bound and twisted with the darkness. Your physical presence exudes an aura of darkness, little wisps of shadow that float and flicker around you like a black flame. As an action you can cause this aura to grow and expand around you into a sphere of magical darkness with a radius of 30 feet.  When you use this feature you may designate up to 10 creatures that are not affected by the darkness, granting them the ability to see through the darkness as if it were simply dim light.

When you use this feature, you may also designate up to 10 creatures in the area as hostile. Hostile creatures must make a Constitution saving throw against your spell save DC , taking 4d12 necrotic damage on a failure and half as much on a success. At the beginning of each turn they begin within the sphere Hostile creatures must make a repeat their constitution saving throws, taking damage the appropriate damage for a success or failure.

This feature lasts for an hour, or until you take an action to dispel it. Once you use this feature, you cannot use it again until you complete a short or long rest.