After William resolves to leave Akiba, Prometheus advises him to take the guild north to Susukino. Several months later, when Shiroe seeks the guild's help with a new and difficult raid, he joins the Abyssal Shaft Raid Party as a member of the fourth party.
Standing at 192 cm, Prometheus is a tall young man with equally-long hair that nearly reaches his knees. He dons a skin-tight leotard under a long, green cloak with a fur collar. Over his gloves, he wears magic rings. In battle, he wields the Staff of Successive Poems as his weapon.
Although he is usually silent, much like his namesake of the Greek Titan he is named after, Prometheus' wisdom and judgement is on par with William's. Like Dinclon, he is loyal to William, and is one of Silver Sword's earliest members. He uses his subclass to quickly discern the enemy's weaknesses.
Round Table Alliance arc
Prometheus is one of Silver Sword's representatives at the Round Table Conference. He stands on the side as the meeting starts, and opens one of the double doors after William announces his decision to leave. Along with the other members of the guild, he follows William in his self-exile from Akiba to Susukino, with Tetora following them.
Libra Festival arc
When Silver Sword arrives in Susukino, Prometheus and Dinclon stand behind William when their guild master confronts Demiqas.
After some Silver Sword members, tired of raiding and afraid of the effects of dying, leave the guild, Prometheus questions what they were going to do next before Dinclon calls them weaklings. William himself says nothing about it.
Gold of the Kunie arc
When Shiroe arrives in their guild hall with a request to assist in the Abyssal Shaft raid, Prometheus is sitting with Dinclon at one of the tables, and watches as Demiqas barges in to challenge Shiroe to a rematch. Later, Prometheus is placed on the fourth team as one of the attack-oriented members.
Prometheus stands over Kawatarou Nakai's body after the latter was killed by Vendémiaire's attack, calling for a healer. He is present at all the strategy meetings, and notes with interest when Shiroe mentions that there were 60 seconds between Vendémiaire's new skill.
When the raid party challenges Ruseato of Seven Prison, he notes to Pororoca that Ruseato's attacks were much stronger than before. After they figure out that there were 90 seconds between Ruseato's usage of Moonlight Death Knell, Prometheus activates his Mystical Gold Ring while noting that as long as they dodged the attack, Ruseato was wide open. However, as he is attacking during the stalemate, he is distracted by the fight and is too late to realize that the gates to the two other Bosses, Ibura Habura and Tarutauruga, had opened, and is killed along with the rest of the raid party.
After William's speech, he agrees to go along with them to take another shot at the raid bosses, planting the guild's flag into the ground.
Prometheus, along with the rest of Silver Sword, participates in the battle against the Eternal Moths. After the Moths disperse with the Shibuya Raid Team's completion of the raid, he stands with the other members as they wait for Upashi to wake up, and witnesses Demiqas' tearful joy when she wakes up and proves to be fine.
Prometheus used a magic ring as his weapon. In between leaving Akiba and arriving at Susukino, Prometheus acquired a new staff as his weapon.
- Staff of Successive Poems: Fantasy-class staff engraved with the "Poem of Actualization" which allows one to freely manipulate magical energy. Shortens the cooldown for attack spells. With this, Prometheus, who's charged with raising the curtain on large scale battles, is capable of unleashing chains of AoEs.
- Mystical Gold Ring: Through the use of a ritual, the concept of sacred mysteries is crystallized into this Secret-class ring. The ring itself looks like a large rhombus. It reacts to magical energy, enhancing its mystic properties, and provides an immense boost in damage to the caster's spells. In the duration of its effect, the wearer's Hate will continue to increase non-stop.
- Mathers' Leotard: Phantasmal robe for clearing the epic quest Piper's Resurrection. Properties include strengthening AoE, raising damage, suppressing Hate accumulation, etc. This robe greatly emphasizes the wearer's bodyline, but Prometheus doesn't seem to be too concerned about this. However, this robe was designed with a female avatar in mind, so doesn't quite fit his physique.
- He shares a Japanese voice actor with Hien, Dinclon, Shigeru, and Aomori.
- In the first anime settings book, Prometheus was listed as a Druid rather than as a Sorcerer.
- One of the Earthling rumors floating around is that Ukiyo, Dinclon, Prometheus, and Pianississimo are all related. In another rumor, William is actually a member of royalty, with Ukiyo as the Court Maid, Dinclon as the Grand Master, Prometheus as the Court Mage, and Pianississimo as the Court Bard.
- In Greek mythology, Prometheus was a Titan who created humankind by forming them out of clay, and stole fire from the gods and gave it to humans.
- His robe, Mathers' Leotard (メイザースのレオタード), may be named after the British occultist Samuel Liddell MacGregor Mathers.
- ↑ Log Horizon Database, Prometheus https://lhrpg.com/lhz/i?id=1178
- ↑ Log Horizon Database, Tomo Mizukusa https://lhrpg.com/lhz/i?id=2976
- ↑ Log Horizon Anime: Episode 9, Round Table Conference
- ↑ 4.0 4.1 Log Horizon 2 anime, episode 3: The Abyssal Shaft
- ↑ Log Horizon 2 anime, episode 9: The Changing Battlefield
- ↑ 6.0 6.1 6.2 lhrpg.com, Silver Sword Raid Party Equipment https://lhrpg.com/silver_sword/
- ↑ Weekly Famitsu: Jan. 5, 2015 Edition
- ↑ https://twitter.com/loghorizon_TRPG/status/737997686738018304
- ↑ https://twitter.com/loghorizon_TRPG/status/738000270974582785
First Party: Dinclon • Ukiyo • Touko • Azalea • HighlandSky • Enkaatanto