Voidblade weapon, very rare (requires attunement)

This blade is a mottled black and blue, with speckles of white throughout it. It’s hilt slowly shifts shape even as you hold it, and when you attack, the weapon leaves a shimmering trail in it’s wake.

Return To Nothing

As an action you can cast Disintegrate, spell save DC 18, targeting an object or a creation of magical force. 
Once used this property of the sword can not be used again until the next dawn.

Wall of Emptiness

As an action you can swing this sword through the air while clearing your mind and focusing on the infinite nothingness of the void. When you do so a rift of stars and darkness appears where your blade was. This rift forms a 20-foot tall and 60-foot long jagged wall extending from you that remains for the next minute. If the wall cuts through a creature’s space when it appears, the creature is pushed to one side of the wall (your choice which side).

Anything that passes through this wall disappears into the void for the duration. When the wall dissipates with a roar any creatures or objects that disappeared into it are ejected into the nearest unoccupied space. 
Once used this property of the sword can not be used again until the next dawn.