An Indigo Knife is vaguely triangular in shape with concave edges on one side of the blade and handle. The middle of the other side of the Knife has a circular cut taken out of it. True to its name, it is entirely colored indigo.
"Indigo" is French, and like its English counterpart refers to a dark color that lies between blue and violet on the optical spectrum.
The Indigo's ground combo is noticeably short, consisting of only two moves. It begins with a two-swipe move, one going up and one going down, and finishes with a low, circular sweep, Knives brandished. From the first move, it can be branched with a -Combo, in which Larxene flips vertically upward, slashing out with her Knives.
The aerial combo of the Indigo is also fairly short, containing only two moves. It begins with another two swipe move, one upward and one downward, then finishes with a mid-air roll ended by a downward swipe.