Gohma

Gohma (also known as Ghoma) is a recurring boss in the Legend of Zelda series. Despite appearing as different enemies in each appearance, the general appearance of Gohmas is that of armored arthropods, characterized by its single tell-tale large eye.

The Legend of Zelda
In the original Legend of Zelda, Gohma is simply a large armored spider in possession of an enormous eye that is susceptible to arrows when open. It shoots fireballs at Link, yet can be defeated by having arrows fired at its eye. Gohma comes in two variants, red and blue; the red Gohma requires one hit with the arrow to kill, while the blue one requires three. It is considered to be the mother of all Tektites.

The Legend of Zelda: Link's Awakening
In Link's Awakening, two small Gohmas act as a miniboss in the game's fifth dungeon, Catfish's Maw. They strafe backwards and forwards across the room, one behind the other. Only when Link is within attack range will they open their eyes, which makes them vulnerable to attacks from the sword, Bow or Hook Shot.

The Legend of Zelda: Ocarina of Time
Parasitic Armored Arachnid, Queen Gohma is the boss of the first dungeon in Ocarina of Time. Queen Gohma is part of a curse placed on the Great Deku Tree by Ganondorf. In order to defeat her, Link must shoot her huge eye with the Fairy Slingshot.

The Legend of Zelda: Oracle of Seasons
This incarnation is very similar to that of the original The Legend of Zelda, however, it more resembles a crab than a spider, complete with quick sideways movement and crab-like claws. The battle against it is similar to the ones in the original. However, instead of immediately shooting its eye with arrows, Link must first slash and destroy its prominent claw and then proceed to shoot seeds into its eye with the Slingshot. It guards the fourth Essence of Nature in the Dancing Dragon Dungeon.

The Legend of Zelda: The Wind Waker
A Gohma serves as the boss of Dragon Roost Cavern, the first dungeon in The Wind Waker. Unlike most other Gohmas, this Gohma has the appearance of a huge scorpion-like creature with tough scales protecting its body. This Gohma is sometimes thought to be the mother of the Magtail species; the visual similarities are extremely clear.

Video
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The Legend of Zelda: Four Swords Adventures
Gohmas appear in two variations. The first type is a large, one-eyed arachnid that aimlessly wanders in The Fields of Hyrule. The second type also appears as a large, one-eyed arachnid; however, it acts as mini-boss and shoots fireballs at Link. Both types of Gohma can be harmed only by shooting arrows at its open eye.

The Legend of Zelda: Twilight Princess
Gohma appears as Twilit Arachnid Armogohma in Twilight Princess and is the boss of the Temple of Time. She appears as a large tarantula with a large, sinister eyeball on her thorax. This eyeball fires a laser beam at Link and also serves as Armogohma's "weak point". Link must fire an arrow at the eyeball to make Armogohma fall to the floor; when she does, Link takes control of one of the nearby statues using the Dominion Rod and crushs Armogohma. Similar to her Ocarina of Time form, Armogohma gives birth to several little spiders who attack Link. After taking serious damage, Armogohma appears to have been destroyed (even cuing the "boss victory" music to begin playing), however, it is revealed that the massive spider body was actually a suit of armour, and that Armogohma's real body consists almost entirely of the eyeball. At this point, rather than attack Link, Armogohma hides in the center of a cluster of her young, and simply flees until she is destroyed.

There are also young Gohmas with blue abdomens that appear as regular enemies in the Temple of Time and Baby Gohmas appear in extremely large swarms in said dungeon.

Name discrepancy
For the earlier Gohma bosses, two spellings - Gohma and Ghoma - were used interchangeably; however, due to the similarity of the bosses regardless of the name, they are usually all referred to as Gohma.