The Freeze Gun is the newest technology utilized by Federation Marines in Metroid: Other M. It is first seen during the battle with the Brug Mass, where Commander Adam Malkovich authorizes the use of Freeze Guns during the battle to attack the massive beast's tentacles, freezing them and allowing Samus Aran to blast them with her Missiles. After the battle, Adam authorizes each member of the team to carry one during their exploration. It seems to be the Federation Marine equivalent of Samus' Chozo-made Ice Beam.
The Freeze Guns seem to have varying levels of effectiveness depending on the organisms they are used on. For instance Maurice Favreau, a human, was killed by being frozen to death. The specific Infant Metroid found at the entrance to Sector Zero met its demise from a single shot of Adam's Freeze Gun. Curiously, he was also capable of disabling Samus' Power Suit with the same weapon. However, it is important to note that keeping her suit active requires inhuman levels of concentration and mental determination, a state her mind was not in due to a recent resurgence of memories involving the baby. Near the end of the game, MB points a Freeze Gun at Samus and Madeline Bergman, eventually giving it to Madeline who later uses it on the android. Though MB was entirely frozen, she remained alive; several Federation soldiers were required to open fire with their rifles at her while she was encased in ice, piercing her body and destroying her.
The existence of this weapon may be more proof that the Galactic Federation was already developing technology similar to Samus', or reverse-engineering her gear, prior to Metroid Fusion. However, Freeze Guns appear to operate in a largely different manner to the Chozo's Ice Beam, namely by shooting some form of chemical freezing agent stored in a tank in front of the weapon's trigger.
- The Freeze Gun is carred in a holster on the right leg similar to Samus' own Paralyzer.
- The sequence that allowed MB to be killed is similar to the method needed to kill a Metroid larva, in which both are first frozen prior to inflicting the finishing blow with a different weapon.
- The effect of the Freeze Gun seems to be stronger than that of Samus' Ice Beam, as a single shot was able to freeze a Magdollite solid, while it takes a fully charged shot of the Ice Beam just to freeze over a Magdollite's mouth. However, this could be gameplay physics, as the Power Beam in Metroid Prime 3: Corruption was much stronger in cutscenes than it was in actual gameplay.