An orphan raised by Nina and Elder Topapa in the village of Ur. Adventurous by nature, his curiosity gets the better of him as he tumbles into a hole created by the great earthquake.
Luneth has long silver hair and violet eyes, and in his Freelancer outfit wears a light purple turtleneck covered by a dark violet sweatshirt and a sienna vest. He wears brown gloves, long light gray pants, black knee-high boots, and carries a light brown fanny pack. His theme color is purple, shown in his Job armor, while his turtleneck collar is visible while robe-clad. The three buckles on his vest are used to distinguish his Job outfits from his allies'.
Luneth is described by Doga and Unei as the light of courage. Sure enough, his tendency to travel recklessly leads him to the Wind Crystal. In the opening FMV, Luneth is a Warrior, reflecting his bravery and will to fight and he will frequently jump into situations despite the dangers. He is cheerful and positive but can be too impulsive or blunt, leading his allies to scolding him.
Luneth and Ingus are shown arguing in the opening FMV, reflecting their opposite personalities, but while the party traverses a cave, Ingus saves Luneth from falling off a cliff. Luneth assumes the de facto role of leader, speaking on behalf of the team and motivating them to continue on their quest. His defending Arc from the bullies in Ur shows he is a leader-like figure among the children.
He is confident but not to the point of arrogance. Luneth is determined to fulfill his goals and keep his promises, getting upset when he believes he's failed someone. He treats everyone in an equal manner, including royalty, and has no qualms about helping strangers. He encourages those more timid than himself and that combined with his determined and more outgoing nature help him become a valuable pillar of support for the party.
Luneth is an orphan raised in the remote village of Ur by the priest Topapa and his foster mother, Nina. Ten years ago, when he was very young, Luneth and his biological parents were dwellers of the surface world below the Floating Continent. While traveling on Cid Haze's airship they were engulfed in a thick, vast darkness and crashed on the Floating Continent. Luneth's parents were killed but Luneth survived together with Cid, who took him to Ur and gave him to the elder Topapa. Since then Nina and Topapa raised Luneth and Arc as their own sons.
At age fourteen, Luneth is exploring the Altar Cave when an earthquake drops him into a pitfall where he finds the Wind Crystal that chooses him as a Warrior of Light and instructs him to find the other three destined. He and Arc venture to Kazus, meeting Refia on Cid's airship, and then Ingus at Castle Sasune, both places cursed by the Djinn. With the help of Sara Altney, they defeat it. The Crystal declares the four to be Warriors of the Light and charges them to defeat Xande, a sorcerer who has flooded the surface world with darkness.
After solving the problems caused by Xande's servants on the Floating Continent, Luneth and the others travel to the surface world where the party teams up with Aria Benett, the last priestess of the Water Crystal. She and Luneth befriend as they retrieve the crystal's shard from the Temple of Water and travel to the Cave of Tides to restore the crystal itself. After she restores the crystal Aria protects Luneth from an ambush by the Kraken at the cost of her life. After the Kraken's defeat, she dies in Luneth's arms.
Luneth's battle prowess is determined by the job he is equipping. He starts a Freelancer, but after making some progress, more jobs become available, and the player is allowed to freely change between jobs and accumulate progress in each. The individual job abilities are expanded, with advanced ones
Having characters progress through drastically different job branches can be both a blessing and a curse, as HP increases gained through leveling up accumulate into the permanent abilities of the character, although HP is the only affected stat.
Luneth has appeared in the following games throughout the Final Fantasy series:
- Pictlogica Final Fantasy as a playable character.
- Final Fantasy Airborne Brigade as an ally and a summonable Legend.
- Final Fantasy Artniks
- Final Fantasy Record Keeper as a playable character.
- Final Fantasy Brave Exvius as a summonable vision.
- Final Fantasy Trading Card Game as a series of cards.
- Triple Triad as a series of cards.
The Onion Knight in Dissidia Final Fantasy has an alternate outfit that is directly based on Luneth. His hair becomes straight, long, and silver. His eyes become violet and his costume color changes, but takes on Refia's coloration, which is possibly in reference to the coloration of the Unnamed Hero Artwork by Yoshitaka Amano. Users in Square Enix Members Virtual World community can make their character appear as Luneth. Luneth's hair costs 100 crystals and his clothes cost 480 crystals.
Despite having been given to a male character in Final Fantasy III, Luneth is usually a female name derived from the Latin luna. Luna means "moon" in Latin, Italian, Romanian, Russian, and Spanish.
- Luneth is the only player character with a unique body armor. He is initially equipped with a Vest that cannot be obtained otherwise; however, it is the weakest armor (together with the Rusty Mail), as it provides only minimal Defense and Magic Defense. A reference to his vest is made in Final Fantasy Brave Exvius as one of the ultimate items he awards the player. It retains its minimal defense, but provides a substantial boost to attack, also likely a reference to Luneth's default Warrior class.
- When the player fights the Iron Giant, Arc will yell out, "L-Luneth!"; however, if the player renames Luneth, Arc will yell, "L-[insert name here]!" instead of changing it to the appropriate first letter.
- Unused text from the game has Luneth acknowledging he got the party captured. This was part of a scrapped Castle Hein sequence where the party would have been split when captured, hence the sentence "3 people rescued! The party was united!".
- Luneth is mentioned in the description for the Wind-up Onion Knight in the Japanese version of Final Fantasy XIV.