The Kingdom of Euclid (ユークリッド王国 Yuukuriddo Oukoku?) is one of the major kingdoms of the present and future eras of Aselia in Tales of Phantasia. Its capital is the City of Euclid, and its boundaries include the entirety of the Euclidian continent and the sub-continent of Venezia to its north.
The kingdom is covered in forests and greenery, blessed as the home of the Great Tree Yggdrasill, as well as the home of the Wind and Earth Spirits. It has a large mountain range on its southern landmass, in which the Catacombs and Volt's Cave are found. Its southern and middle sections are connected by a mountain pass, while getting from middle Euclid to the Venezian sub-continent requires crossing two bridges. Euclid and its Venezian sub-continent are home to the town of Toltus, which is Belladem and Miguel in other times, as well as the cities of Euclid and Venezia. Morrison's Home is located on it, and in the future, a school for magic derived from Morrison's teachings is also found on its southeastern tip. In the past, it is also home to Hamel.
- Belladem/Toltus/Miguel - Cress Albane and Chester Burklight's hometown, situated right before the Forest of Spirits. It is a small, peaceful village with a name change in every era.
- City of Euclid - The capital of the continent and the kingdom named after it. It grows from a small village to a bustling city.
- Hamel - A small village between Lone Valley and Venezia. Its villagers are devout to their religion.
- Venezia - The major port city of Euclid. Its ships can travel to Alvanista and several smaller locations.
- Morrison's Home - The home of the Morrison family. It is a large building removed from the rest of civilization, but successive generations of Morrisons make their home there.
South Forest/Forest of Spirits
The forest where the Great Tree Yggdrasill and its guardian Spirit Martel make their home.
The Catacombs (地下墓地 Chika Bouchi?) is found to the south of Toltus in the present. It is the location where the Ancient King Dhaos is sealed by Trinicus D. Morrison, Meryl Adenade, and Miguel and Maria Albane. A stone structure possessing walls lined with old statues, there are coffins containing both zombies and items in its rooms. At its lowest levels are electrified floors and a lava-filled room requiring the "Raise Ruby" to traverse via special gylphs that cause the user to fly. The final room is a highly-stylized ritual room, with a magic circle on the ground surrounded by four giant statues, and Dhaos's tomb is at its center.
Mars Uldole heads here after obtaining the pendants required to unseal Dhaos, and Morrison follows him, with Cress, Mint Adenade, and Chester at his heels. Unfortunately, they are unable to stop Mars from unsealing Dhaos, and Dhaos proceeds to kill Mars for thinking that he could control him. Dhaos turns his attention to the others, but Morrison manages to send Cress and Mint to the past for help. Not long afterward, they return, with allies Claus F. Lester and Arche Klein in tow. They manage to defeat Dhaos, and the Catacombs collapse around them. While the group flees to safety, Dhaos's body is crushed by the ruins. A book in the future Euclid Castle mentions that the Catacombs may have been created by the Maeglan Clan who ruled the southern part of the continent in the past, and it references the fact that the Catacombs were destroyed in the present timeline.
Demitel's Mansion (デミテルの館 Demiteru no Yakata?) is a mansion located on the Isolated Island of the West, which is to the northwest of Euclid and home of the half-elf Demitel. The island itself covered in plant life, and the ocean streams into a small lake at the base of the mansion, but it is covered by perpetual fog. Demitel's work room is well hidden; before even getting to the monster-filled basement, someone must obtain the key from his room to unlock a door to the garden that keeps light from flooding into the main room, only the window is guarded by an "Orcrot".
The aspiring burglar must then focus the light in the lobby onto two crystal balls using two prisms. After seeing the destruction at Hamel, Cress quickly jumps to Rhea Scarlet's vengeance-backed cause. They storm his mansion after hitching a boat ride from Venezia to confront Demitel. Demitel dismisses them, stating that he would never hurt the Scarlets to whom he viewed as his masters and that Rhea looks nothing like the true Rhea. Cress, however, notices that Demitel has a hooded skeleton reflection, much like Mars had, and discovers him to be one of Dhaos's minions. They proceed to battle and defeat him, and Rhea thanks them before moving on, relinquishing Arche's body, which she had been using.
Lone Valley (ローンヴァレイ Roonvarei?) is found between Euclid and Venezia. It contains greenery leading to a high cliff occupied by a lone tree, and it also has a network of caverns where the barrier between Aselia and Daemonium is weak, which can cause miasma to leak over. Lone Valley is the home of Sylph, the Wind Spirit. In the past, it is where Arche and her father, Bart Klein, live in a home at the Valley's entrance. Their house is inhabited by an old man in the future.
In the past timeline, Claus heads here with Cress and Mint on a tip. At the entrance, Bart asks them if they have seen his daughter, and upon hearing a negative, asks that they keep an eye out for her. The party then discovers that the Sylph living in the Valley have begun acting bizarrely, and Claus finds the source to be miasma, the wind of Daemonium, which not only has a negative effect on the Spirits, but also hides powerful foes. Plugging the pools of miasma with rocks, the party heads to the peak, where Sylph, in gratitude, makes a pact with Claus. Sylph also directs them to the Forest of Spirits to see Yggdrasill and its guardian Spirit Martel. Many years in the future, in Tales of the World: Summoner's Lineage, the summoner Fulein K. Lester heads the Lone Valley at the advice of the Euclidian King. Here, he finds Mark Ginihle fighting and comes to his aid against Sylph. Mark tells Fulein that he is searching for a "Spirit Ring" for his revenge, and Fulein suggests that they join forces, an offer that Mark reluctantly accepts. Fulein gains the "Sylph Ring" here, allowing him the power to summon Sylph.
Cavern of Spirits
The Cavern of Spirits (精霊の洞窟 Seirei no Doukutsu?) is located to the northeast of Belladem/Miguel. A dark and dank cave, it has multiple water sources running throughout it, and it is home to the Earth Spirit Gnome. Many doors guard the entrance to its depths, and the very first door requires the password "Kikurin", which a man in Alvanista will sell. In the past, the party heads here to form a pact with Gnome. Numerous Gnomelets block the path to where Gnome rests, however. The first batch requires the party to lead a lost Gnomelet back to its group while dodging the dangerous "Clay Idols" that litter the path. Once reunited, the group disperses, allowing the party further entrance. A second group needs the party to activate an alarm to cause the guards to abandon their post. Only then is the party allowed to meet Gnome, who requests battle. After subduing him, Claus forms a pact with Gnome.
Many years in the future, in Summoner's Lineage, Fulein and his group head to the Cavern of Spirits on the tip that Alph Ginihle, the person Mark is searching for, is going there. At the Cavern, Mark confronts Alph over the death of his parents in Venezia seven years ago, but Alph barely responds. When defeated, Alph says that if he has to abandon the "Gnome Ring", he will head for the "Efreet Ring" next. Elmira Louge reasons that they need to head to a fiery place for the ring to the Fire Spirit, and Fulein realizes they need to go to Freyland. Mark also reveals that Alph is his older brother and that he killed their parents seven years ago.
Limestone Cave (浸食洞 Shinshokudou?, "Erosion Cave") is located on the Isolated Island of the North Sea, which is to Venezia's north. A water-filled cave with water levels controlled by switches, the Water Spirit Undine makes her home here. With numerous passages that may be rendered impassable depending on the height of the water, determining how to advance is a puzzle in itself. In the past, the party heads here in order to find Undine. Navigating the twists and turns of the place, as well as the changing water level in order to reach its lowest depths, they find Undine, who immediately attacks them upon disturbing her rest. Subduing her, Undine assents to a pact, and Claus gains the ability to summon her.
Upon stopping by in the future, the party decides to take a break and have a picnic. Unfortunately, Arche has a hand in creating the food, and she inadvertently gives the group food poisoning. After returning, Mint cooks the food this time, and the men in the group praise her. Mint then suggests that all Arche needs is some help. The other party members try to stop her, but both women come back with food that they are hesitant to try. They discover that the food is actually good, but they attribute it for to Mint's skills being good enough to balance out Arche's horrible ones. Many years in the future, in Summoner's Lineage, after recruiting Elmira to their group, Fulein and his friends head toward Limestone Cave, where the "Undine Ring" may be found. Finding it, they are confronted by Undine herself, who they must defeat. Upon doing so and obtaining the ring, they are at a loss for where to go. Mark suggests heading for the nearby port of Venezia, where people are always coming through, in order to obtain information.
Volt's Cave (ヴォルトの洞窟 Voruto no Doukutsu?) is a cavern on the future Euclidian continent, located near the collapsed Catacombs. It is a cave where its doors are controlled by switches and generators that require power, and the Thunder Spirit Volt makes its home here. Speed and precision are required to advance before the doors close on unsuspecting adventurers.
In the future timeline, because the seas are rendered impossible to cross due to Dhaos's influence, the party attempts to find Volt to power their Techbirds. At the entrance, however, they find a young girl fighting against several ninja, only to have all combatants enter the cave upon sight of them. Inside, they find the young girl in an electrical trap, and they free her, only to have her flee again. Using the Sorcerer's Ring to power generators and throw switches, the group heads deeper into the cave, where they once again find the girl attempting to defeat a group of ninja. Cress, at the prodding of his friends, steps in and saves her, for which she thanks him and reveals her name, Suzu. She leaves, and the group heads to the final room, where Volt rests. By defeating Volt, Claus makes a pact with it and gains the power to energize their Techbirds for flight.
Many years in the future, in Summoner's Lineage, after finding Mint's Unicorn Horn and summoning her into the future, Fulein is directed by Claus to Volt's Cave to find the "Volt Ring". Unfortunately, the group stumbles upon Alph there, who has the same purpose. At the beginning of the battle, Chester explodes at Alph for abandoning his younger sibling, and they being to fight. Upon Alph's defeat, he relinquishes the "Volt Ring" but warns the group that they are still too weak to face Xex. Chester is surly afterward, and Cress explains that Chester had lost all of his family, including his little sister, Ami Burklight. Velga Montor understands his sentiments. Claus then directs the party to the Tower of the Zodiac, where Luna's ring lies.