Crescent Unit Circulus is an enemy from Crisis Core -Final Fantasy VII-.
He is among the strongest of the Crescent Unit enemies with access to the Energy spell in addition to chaining attacks with Chain Thrust. Powerful attacks—such as Tri-Thundaga, Energy, or Flare—should be used to deal with him as quickly as possible. In groups, he should be left for last as his attacks aren't hard to dodge.
Circulus is Latin for "circle" or "ring."