Groganches reside in three locations within the BOTTLE SHIP. The first location is a Swamp Zone in the Biosphere. The second location is also in the Biosphere in Experiment Floor 3. The third location is in the Cryosphere's Experiment Floor, just outside the Materials Storehouse.
The bioform is composed of six spidery legs; an elongated head (resembling that of an ostrich or giraffe), mounted on a thin, jointed neck; and a central core which is adorned with a large, orange bulb on the underside. The creature's skin is very similar to that of tree bark, allowing the creature to easily blend in with forest environments.
The Groganch's defeat will result in the large bulb going from orange to green, as well as a loss of color in the creature's eyes. Strangely, a close look on the bulb at this point reveals a translucent outer shell containing a smaller spherical structure inside; it is unknown to what purpose this inner bulb serves.
The Groganch's legs also have a 360-degree rotation radius, allowing it to merely rise up backwards when on the ground as opposed to getting up manually. This results in two different forms of the Groganch: a smaller, more mobile to-the-ground form resembling a spider, and a taller, lumbering form resembling a sauropod's.
During a battle, a Groganch primarily attacks with globes containing noxious gasses. These globes are fired from the center of its body, regardless of the Groganch's current orientation. Upon impact, they explode and release their purple gas. Samus can either dodge or shoot the globes before they reach her. It can also perform a wild charge where it attacks with its head and legs.
To defeat a Groganch, Samus must target the large bulb with Missiles or her Beam. After enough damage the creature will flip itself over, with the bulb now on its back. In this form it will continue to fire globes, but its charge is replaced with a body slam it performs if Samus goes underneath it. Continuing to shoot the bulb (either by entering Search View, or by climbing nearby terrain) will eventually cause the Groganch to flip over again. This cycle will repeat until it dies. Its body remains in the area it fell until Samus leaves the room.
It is possible to use Overblast on the Groganch by jumping on the bulb while it is located on its back. Samus must go underneath the Groganch to lure it into body-slamming, lowering the bulb so that Samus can jump on it and execute the Overblast. If Samus fails to fire, however, the Groganch will flip its body over again with her still on the bulb, slamming her into the ground to cause massive damage.
- Samus in the Cryosphere Drifts
- "Sector 2 of the Bottle Ship was called the Cryosphere, and its sub-zero temperatures sustained many recognizable Zebesian life-forms. One was new to me - a massive creature with a spiderlike body that lobbed globes containing noxious gas. As I first encountered it in the Biosphere, it was obviously adapted to many environments."
"Groganches are terrifying creatures made from trees. The giant sphere at the center of its body is its weak spot and cannot be damaged elsewhere."
- In the Biosphere, a glitch will occasionally cause the Groganch to become stuck against a pipe bundle and walk endlessly without ever actually changing position. This makes the creature rather easy to defeat, as Samus can fire on the bulb while remaining out of range of its projectiles.
- There is an observation deck in the Biosphere with two Groganches that are much larger than the others behind glass that cannot be reached, but they can be killed once the Wave Beam is obtained. Killing them offers Samus no reward.
- The Groganch's bulb resembles a Kashh Plant, and is shared by the Dragotix.
- The Groganch's dual plant-animal nature is shared by another Biospherian creature, the Gripper. However, it is unknown whether the two species are at all related.
- The Groganch's head and ostrich-like qualities strongly resemble that of the Dachora.
- Concept art of the Groganch states that it lays eggs.
- The Groganch's battle theme is an abridged version of The Burning Lava Fish.