The Eccentric Vase is an unlockable Equipment item in Risk of Rain 2.
Completing the Blackout Challenge unlocks this item.
Activating this item creates a quantum tunnel. A quantum tunnel is two spheres connected to one another by a faded line. One sphere will spawn on the player, and the other one will spawn where their reticle is. The tunnel won't be created if the players reticle was pointing towards something that is outside of the map's boundaries.
A quantum tunnel
Pressing the interaction button on either sphere will move the player along the faded line towards the other sphere. During that time, they may exit the tunnel at any time by pressing the same button. They will maintain the velocity they had while moving in the tunnel when they exit, potentially throwing themselves off the map.
The player can be hit while in the tunnel.
A player inside the tunnel