|“||The creature's corpse showed signs of what looked like Metroid predation, making my mind race. Metroids... here? Impossible. Metroids can't tolerate cold temperatures - they couldn't survive in this environment. Besides, they're extinct. The baby was the last of its kind...||„|
The first Gigafraug is found in a large cavern and attacks Samus atop a frozen lake. The creature's eyes glow bright green when it is in battle. It will attack without provocation, trying to crush Samus with its enormous head. The lumbering beast can also jump in the air and then land directly on top of Samus, even if it is facing away before jumping.
Unless the Plasma Beam is used, a Gigafraug is immune to Lethal Strikes (though it will still flash red, indicating damage) until its head is broken by firing a Missile at it. If Samus attempts to Overblast before breaking the Gigafraug's shielded head, the creature will headbutt her away. Alternatively, it can be damaged with attacks to its unshielded rear, like a Moto. Once Samus authorizes the Screw Attack, she can use it to kill a Gigafraug in one hit like many other creatures on the BOTTLE SHIP.
A particular Gigafraug is found in a frigid room frozen and dead. Samus observes the deceased form and remarks that it looks like it was drained of its energy by a Metroid. She dismisses this as impossible not only due to their species recent extinction, but also because Metroids cannot survive cold temperatures. The Gigafraug being drained by a Metroid is later proven true with the existence of unfreezable Metroids.
"Gigafraugs are ferocious, fighting bull-like creatures. They can charge at Samus as well as jump press, but they are easy to counter by using Sense Move."
- The Metroid-predated Gigafraug body is not present during the post-credits sequence. The corpse was most likely disposed of, as no Gigafraugs were encountered on the Biologic Space Laboratories research station, if any ever were on board.
- The Gigafraug appears to have physical traits seen in several animal species of Earth, such as antlers like that of a moose and a fluke on its tail like a dolphin (the latter characteristic may suggest the creature is an aquatic bioform), while its head shape resembles that of a whale.
- The Gigafraug's squat, bipedal body structure heavily resembles that of the Moto, the Grenchler, the Grapple Guardian, the Sheegoths and Baby Sheegoth. It is unknown if the creature's designs were inspired by one another in any way.
- Its name appears to be a combination of the metric prefix "giga-" (referring to its large size) and a misspelling of "frog" (referencing its amphibious qualities).
- The Gigafraug is one of the only creatures in Other M that Samus can use to her advantage. If she dodges its rush attack at just the right time while standing in front of breakable icicles, the Gigafraug will shatter them for her. This is most notable in the "ice bridge cavern".