Diarn (ダイヤーン Daiyān) is a flying diamond-like enemy from Mega Man 9 that appears in Jewel Man's stage and the third Wily Castle stage. When moving, it is invulnerable to every weapon except Black Hole Bomb or Tornado Blow. It periodically stops and opens to shoot a projectile. During that time it is vulnerable.
- In Diarn's sprites, it possesses a mouth and a rounder body in comparison to its artwork.