Abyss Worm Abyss Worm , also known as AbysWorm , Lunar Worm , and Red Worm , is a recurring enemy in the series . It is often the most powerful worm in the games it appears in , if not one of the strongest worms . Abyss Worm made its debut in " Final Fantasy II " . Appearances . " Final Fantasy " . Abyss Worm is a rare enemy fought exclusively in the GBA and later releases at Earthgift Shrine in the desert areas , and are usually fought alone or in pairs . Abyss Worm is a highly dangerous enemy , being the strongest of the Worm family , having access to very powerful physical attacks . It possesses the highest HP of any regular enemy in the game as well as very high Magic Defense . Upon defeat , it may drop the very valuable Megalixir . " Final Fantasy II " . Abyss Worm is an enemy fought at Jade Passage , and is a considerable threat to the party , attacking in groups of three or more . Abyss Worm will attack with very powerful physical attacks in conjunction with its Cyclone XIII attack , dealing very heavy damage to the party . Abyss Worms absorb Fire - elemental and Death - elemental attacks , and resists Body and Mind attacks . " Final Fantasy IV " . Abyss Worm appears as an enemy fought around the Red Moon and Lunar Ruins . It is the strongest Worm in the pre - GBA versions , with the Gigas Worm being stronger . It attacks with physical attacks and Bloodfeast , and can counter attacks with Bloodfeast . It is weak to Fire - elemental attacks . " " . Abyss Worm returns as the second strongest worm in the game , beaten by the Backed Worm . It appears during the Crystals Tale around Kaipo and Damcyan , as well as the Subterrane , and is otherwise identical to its previous incarnation . " Final Fantasy VI " . Abyss Worm is a boss fought at Dragons ' Den in the GBA and later releases . It fights using a regular attack , Acid , 50 Gs , Landslide , Magnitude 8 , Gravity Bomb , and Shockwave . However , due to its low Magic , most of its non - physical attacks deal little damage . Unlike previous incarnations , Abyss Worm is immune to Fire - elemental attacks , but is weak to Holy - elemental attacks and absorbs Ice - elemental attacks . It is immune to all other elements . " Crisis Core - Final Fantasy VII - " . Abyss Worm is an enemy fought during Mission 9 - 6 - 1 : Toughest Monsters and Mission 9 - 6 - 3 : Weapons Gone Haywire . It is the strongest of the Worm family , having high Attack and Magic and access to the abilities Absolute Stop Thread , Osmose , and AP Gravija . It has low Defense and Magic Defense , and can be interrupted by attacks , so it is highly vulnerable to all types of attacks , in addition to being weak to Ice - elemental attacks . It is valuable for its rare steal , the SP Master materia . " Final Fantasy VIII " . Abyss Worm is an enemy fought at Galbadia in the Dingo Desert and Great Plains of Galbadia , Esthar in the Kashkabald Desert and Talle Mountain , and Ultimecia Castle at Elevator Hall , Treasure Room , Passageway , Courtyard , and Clock Tower . It is not a very difficult foe , having access to the abilities Protect , Shell , Aero , Sandshake , and Saliva . At higher levels , it is possible to draw Tornado from them , making them a good enemy to stock from , in addition to Quake , and are the best source of Windmills . " Final Fantasy X " . Abyss Worm is an optional boss fought at Monster Arena after capturing at least one of each fiend in Bikanel . It is the most powerful Worm in the game , and fights very similarly to them with the usage of Swallow , Regurgitate , and Earthquake . However , it deals very high damage with its attacks . When defeated , it drops weapons with Strength + % abilities with Strength + 20 % being a fixed ability , and armors with Defense + % abilities with Defense + 20 % being a fixed ability . " Final Fantasy XIV " . An Abyss Worm appears as part of the Ouranos encounter in Copperbell Mines ( Hard ) , circling beneath the sand in the center of the room and damaging anybody on top of it . It occasionally starts searching for fodder , and if it isn ' t fed will suck the party to the center of the sand pit and deal massive damage to all players . This can be avoided by moving one of the Crystallized Rocks on the outer edge of the arena to the sand pit , as the worm will instead devour the rock . The Abyss Worm cannot be directly targeted by players , and will despawn upon Ouranos ' defeat . " Final Fantasy Mystic Quest " . The Leech enemy is known as the Abyss Worm in the Japanese version , and is the strongest of the worm family . It can be found in the Great Tree .