In the Anime only, the Red Uncanny Sword takes the form of a completely red, bright glowing version of the original Uncanny Sword, which later powers up to a gigantic version as Black☆Star is about to attack Mifune. The true potential of this form is unknown, but one can assume that it gives its meister a tremendous boost of power. After Black☆Star chooses his own path and promises The Will of Nakatsukasa that he'll take up the burdens of the lost souls and save them from their fears, he was granted full control of the Uncanny Sword's powers. Due to this, Black☆Star is no longer covered with markings when activating the Uncanny Sword. It also remains notably longer from this point on, as a reference to his full control. Then Black☆Star rises again after the fatal blow from Mifune and charges towards him. This form is what Black☆Star ultimately uses to defeat Mifune after he spares him to rescue Angela Leon and to work at DWMA.