Tristia of the Deep-Blue Sea

• Name — Tristia of the Deep-Blue Sea • Ja Kanji — 蒼い海のトリスティア • Genre — Adventure, Fantasy, Mecha

• Developer — Kogado Studio, Kumasan Team • Publisher — Kogado Studio (PC) Nippon Ichi (PS2) • Genre — Music video game, Visual novel • Platforms — PC, PlayStation 2, PSP • Released — July 20, 2002 (PC) March 25, 2005 (PS2) August 9, 2012 (PSP) January 20, 2023 (Switch)

• Type — novel • Author — Syogo Mukai • Illustrator — Eeji Komatsu • Publisher — Enix • Published — November 15, 2002

• Type — manga • Title — Aoi Umi no Torisutia ~Nanaka no Hatsumei Koubou Nikki~ • Author — Sakuya Yuki • Publisher — MediaWorks • Magazine — Dengeki Daioh • First — April 2004 • Last — November 2004 • Volumes — 1

• Type — ova • Director — Hitoyuki Matsui • Studio — Ufotable • Released — April 23, 2004 • Episodes — 2

• Type — novel • Author — Takashi Aki • Illustrator — Kawase Yuki (ufotable) • Publisher — MediaWorks • Published — November 10, 2005 is a PS2, PSP, and PC game, developed by Kogado Studio. This game is part of the Deep-Blue series along with the sequel, Neosphere of the Deep-Blue Sky and Akatsuki no Amaneka to Aoi Kyojin. The story has been adapted into an OVA, and has been released with a title of "發明工坊" in China, Hong Kong, Taiwan, U.S.A., Russia, and Poland.

Tristia of the Deep-Blue Sea is a simulation game in which the player's goal is to rebuild the city of Tristia. The player takes the role of Nanoca Flanka and must build an array of technological gadgets using schematics and various raw materials that can be encountered in-game, and sell them to people of Tristia. As new gadgets are introduced to the town, the town is able to produce a greater variety of items and gradually grows.

Tristia was a beautiful seaside town that slowly fell into ruin and dilapidation after being invaded by a dragon ten years before the start of the game. The people of the town tried in vain to rebuild the city in the hopes of restoring it to its former glory. Hopeless, the people decided to send for Prospero Flanca, a legendary inventor who was well known for reviving many dying cities. They received an answer from Prospero, but to their confusion, it was a girl who arrived at the port of the town. That girl was Nanoca, Prospero's granddaughter, and she has been assigned to manage the renovation project.

• voiced by Ayako Kawasumi • The 14-year-old protagonist of Tristia and the player's character. She is the granddaughter of the renowned inventor Prospero Flanca. Prospero's name was well-known all over the world as an inventor and builder, and she is keen to uphold the name. She came from the Imperial Capital with Stuka, an artificial creature, and Tenzan, a mech-styled golem. • voiced by Marina Ōno • The young chairperson of the Carat Firm. She is fifteen years old, and is known as an unyielding and carefree person. She has been into many troubles since Nanoca came to town. • voiced by Sakura Nogawa • A rich girl, 12 years old and classmate of Nanoca in the Imperial Capital Youth Academy. She came from the Hampden clan, a wealthy capitalist family from the capital. Nene adores Nanoca very much, and is the one who recommended Nanoca to the town for the mission. • voiced by Akane Tomonaga • The mysterious girl who was found in a casket recovered from the sea in the vicinity of Tristia. Nothing much is known about her. • voiced by Jūrōta Kosugi • Nanoca's watchdog and support. • voiced by Daisuke Kirii • A golem under the command of Nanoca. It is shaped like a mech. • voiced by Kanoko Hatamiya • The head priest in the Ryunant temple in the city of Tristia. She noticed the talent of Nanoca upon her arrival. • voiced by Tarusuke Shingaki • Deputy Mayor of Tristia and a childhood friend of Reygurett. • voiced by Ryo Ueki / Syoto Kashii • Mayor of Tristia. His name is almost certainly derived from the name of New York's former Mayor, Rudy Giuliani. • voiced by Hidetoshi Nakamura • Imperial multi-millionaire that lends his financial support for the revival project in Tristia. • voiced by Saeko Chiba • Character who appears in the OVA and manga. Self-proclaimed rival of Nanoca since their years at the academy, always coming in second to Nanoca in every competition.

The opening and ending theme song of the game is "UP TO ME!!" by Sakura Nogawa, who voices the character of Nene Hampden. For the 10th anniversary celebration, this game was re-released on the PSP on August 9, 2012. It was re-released as Tristia: Legacy on the Nintendo Switch & Steam in 2023.