The AIM-109 Medusa was a small, trans-atmospheric capable, ship-to-ship (or air-to-air in atmosphere) guided missile, designed to replace the was an update of the Great War-era AIM-104. Designed for launch from small mobile platforms such as starfighters, it was most effective against Covenant single ships such as the Seraph-class starfighter, being capable on most occasions of destroying it with either a direct hit or a close proximity detonation. The Medusa featured several homing systems to prevent it being jammed by enemy countermeasures, and an advanced HEAT tandem warhead with kinetic energy penetrator. This was most effective at destroying targets with a direct hit but could heavily damage them even with a near miss. The AIM-109 featured both contact and proximity detonation systems