Allsmoke

The Item is a common Sickle until the wielder reaches level 3 (When the item deems the wielder worthy). The Sickle emits smoke all around it and forms a smoky duplicate of itself. The Weapon levels up along with the it's owner and gains abilities at certain levels. The abilities can only be performed by the wielder that the weapon deems "worthy". If an unworthy creature touches this weapon they take 2d6 necrotic damage. This weapon also becomes a magic weapon.

You have a +2 bonus to attack and damage rolls made with this magic weapon.

Every attack with this weapon deals necrotic damage

Level 3 (Contact High):

The Sickle's duplicate can be thrown with a range of 60 feet. As long as the Allsmoke is equipped, the wielder can summon back the duplicate after it is disarmed or thrown. As a reaction, the wielder can can use a spell slot to give disadvantage to an attacking creature. 

Level 7  (Cross Fade):

When the wielder lands a hit with either the Allsmoke or its duplicate, the blood from the target causes the weapon to sharpen temporarily. On the next attack, the wielder has advantage and + 3 is added to the damage roll

 

Level 11 (Special Technique):

Once per short rest the wielder can use this technique. The duplicate sickle turns into a shadow duplicate of the wielder with half of the wielder's hit points. The duplicate obeys the wielder's commands and can perform any action within the confines of the rule book. The Smoke clone fights with two smoke sickles that it can throw and summon back to itself. It cannot speak, but it understands all languages. The Smoke clone disappears after 1 minute.

Proficiency with a Sickle allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, Damage: Necrotic, Damage, Combat, Light, Nick