The RGM-89S Stark Jegan is a mass-production anti-ship assault mobile suit. First appearing in Char's Counterattack Mobile Suit Variations line, it was later redesigned for the novel/OVA Mobile Suit Gundam Unicorn.

The Stark Jegan is a special forces-use version of the RGM-89D Jegan D Type designed for anti-ship warfare, and has improved performance due to the additional armor and thrusters. It also incorporated feedback from its prototype, the RGM-89S Prototype Stark Jegan, and can mount missile pods on its shoulders for support use. Thus, it also inherited the functional concept of the RGM-86R GM III. Some of the added armor and the missile pods can be purged when required, with the subsequent balance adjustment being performed automatically.