The Sword of Resonance is the sword of the Skull Knight from Berserk. The Skull Knight forms it by taking the sword and sliding it down his throat, similar to a sword swallowing trick. This fuses the sword with the countless Behelits that he has previously swallowed and stored in his body. It is unknown what the sword's true powers are, but the Skull Knight has used it more than once to slice open portals across different dimensions.
