Subtly

Subtlety rogues are the masters of the shadows, and they strike unseen. They don’t have the lethal poison-tipped daggers of the assassin or the brawling prowess of the outlaw, but their acumen on the battlefield and ability to hide in plain sight are unrivaled. Some claim the art of subtlety looks like malevolent shadow magic—but no matter from where their power is derived, these rogues are capable of performing devastating assaults on their enemies, slipping away unharmed to strike again without detection. Most rogues train their entire lives to learn how to walk in the shadows—subtlety rogues were born there

Backstab

Starting at 3rd level, every time you attack a target from the rear, you gain additional Sneak Attack die when you strike a target from behind. At 9th, 13th, and 17th level, this increases by an additional die, for a maximum of 4 additional Sneak Attack die at level 17.

Premeditation

Starting at 9th level, if you spend 1 minute observing a target before attacking them, you have Advantage on attacks against them for the duration of the encounter.

Shadowstrike

Starting at 13th Level, as a bonus action, you may step through the shadows within 30 feet of where you currently are. You strike with your Main Hand as you emerge, and deal Sneak  Attack damage if you hit. You may use this ability once per short rest, and gain an additional use of it at 16th and 19th level.

Shadow Dance

Starting at 17th level, once per Long Rest, you can step through the shadows for a number of feet = to your Movement Speed, appearing behind enemies as you go and gaining an attack against each of them. After you reach your maximum movement, you return to your original position. You can move to the same shadow multiple times, but cannot move a number of feet greater than your maximum Move Speed. These attacks have advantage and the benefits that come with it.