[NGC 2] Sylvarant and Tethe'alla are inhabited by humans as well as elves, a race of long-lived humanoid extraterrestrials who originated from the giant comet Derris-Kharlan and can manipulate mana to cast magic.

The organization Cruxis is led by Yggdrasill, a half-elf whose ultimate goal is to turn all people into lifeless beings in order to bring about an age free of discrimination.

Yggdrasill's secret identity is that of the legendary hero Mithos, an ageless half-elven boy who seeks to revive his older sister Martel, whom he propped up as a goddess following her death in the ancient war.

The Renegades, a group attempting to thwart Cruxis' goals, are led by Yuan, a half-elf who aided Mithos in ending the ancient war and was engaged to Martel.

When Yuan declares his intent to secure Lloyd to further the Renegades' purpose, the party escapes for Tethe'alla, where they restore Colette's humanity after crafting a Key Crest for her Cruxis Crystal.

Mithos misinterprets this sentiment as a wish to leave the two worlds for Derris-Kharlan, but is seemingly killed by the party before carrying out his seizure of the Great Seed, and Genis keeps his Cruxis Crystal as a memento of his sole half-elven friend.

[NGC 6] On May 8, 2002, Namco and Nintendo announced at a Tokyo press conference that they would collaborate on a number of titles for the GameCube, including a new installment in the Tales series slated for a July 2003 release.

[26] To increase the North American version's appeal to Western audiences, localization producer Nao Higo replaced "Starry Heavens" with an orchestral anthem by composer Motoi Sakuraba, and focused on hiring experienced voice actors such as Scott Menville, Tara Strong, and Cam Clarke for the English voice-acting.

The second novel series is titled Tales of Symphonia: Radiance of Time (テイルズ オブ シンフォニア 久遠 の輝き, Teiruzu Obu Shinfonia Toki no Kagayaki) and is written by Sera Yajima.

[80] Jonathan Metts of Planet GameCube said that although the game "clings to many of the well-worn RPG elements", its distinct battle system, story, and visual presentation allowed it to stand on equal footing with the most recent Final Fantasy titles.

[69] Benjamin Turner of GameSpy said that the lush artwork and innovative battle system characteristic of Tales games helped Symphonia stand out in the GameCube's "RPG-starved" library.

[80] Metts explained that it "strikes a perfect balance between the strategy of traditional menu-based RPG battles and the fast, skill-based action found in a weapons-based fighting game like Soul Calibur".

[71] Daryl Vassar of G4techTV cited the battles as the game's high point and claimed they were fun enough to win over non-RPG fans, though he considered the summoning system — which requires a character to take a great deal of damage before performing such an action — to be a weakness.

[73][77] Irwin negatively compared the amount of backtracking in the game's vast overworld to The Legend of Zelda: The Wind Waker, but was thankful for the various modes of transportation that were continuously introduced.

[71] Smith, however, disliked the lack of detail and facial expression in the character models, remarking that "the rare occasions where they do show emotion come across as disturbingly jarring".

[e] Jastrzab was stunned by the lack of slowdown during the game's chaotic action segments,[80] Turner was also amazed by the consistently high framerate, which he regarded as "a great bonus in a time when most RPGs are content to chug at 30 [fps]".

[68][80] Fahey and GameSpot's Bethany Massimilla remarked that the game's attempt at depth of field effects in some scenes resulted in the characters appearing smeared rather than out-of-focus.

[69][74] The overworld's presentation was criticized as underwhelming; some compared its level of detail to titles from the previous generation of consoles,[72][77][79] while Jastrzab argued that the quality would not have been passable even in that context.

[74] Reactions to the music were mixed; some regarded the score as unremarkable,[70][72][75] which was a source of disappointment for Fahey, as he felt the "beautifully constructed" world deserved a more impressive soundtrack.

[69] Jastrzab deemed the music "exceptional" and "stellar", saying that it "captures the mood of the relevant scenarios with virtual perfection while avoiding the repetitious nature of anything related to anime".

[69] Although Jastrzab approved of the voice acting's professional quality, he mentioned that some of the dialogue was not well-placed, explaining that "There is no building of feeling or creation of tension, it pretty much bursts onto the scene".

[77] Turner also deemed the voices to be "so-so", opining that while the characters' battle vocalizations were sufficient, the actors lacked the range needed for the more emotionally demanding cutscenes, which he said were held back by "generally inept" direction.

[78] Jastrzab argued that the story held a "never-ending" depth underneath its surface, which he said was highlighted by the variety of plot outcomes that arose from subtle decisions by the player, though he warned of the script's excessive moralizing.

[79] Star Dingo compared the story's combination of "heart, warmth, humor, sadness and peril" to the works of Rumiko Takahashi, and proclaimed the writing to be some of the best among console RPGs, elaborating that "the tragedies really strike home, and the characters all have distinct voices, speaking their lines with a welcome sense of subtle irony and self-awareness about RPG clichés".

[84] Kirstin Swalley of Hardcore Gamer considered the combat simplistic but enjoyable due to the small depths granted by its mechanics, though she warned that it may initially feel clunky to players more accustomed to modern Tales titles.

[85] Robert Ramsey of Push Square observed that, by modern standards, the combat was relatively basic and the controls were slightly stiff, but neverless deemed the fights satisfying because of their pace.

[88] Vogel cited the same difficulty, remarking that the battles felt stiff compared to similar hack 'n' slash combat featured in Ys VIII: Lacrimosa of Dana and Kingdom Hearts II.

He added that the inability to cancel out of attack animations, which would incentivize careful timing and skill usage, was complicated by a fast battle pace that encourages reactive and reckless tactics.

[83][85] Swalley complimented the key locations as solid and said that the increased crispness and clarity of the character models enhanced their detail and expressiveness, though she felt that some textures "could have used more work".

[86] Dekker opined that the rareness of neat resolutions to conflicts improved the story, and he proclaimed that the game's cast is still the best in the series, although he said that some awkward localization held these elements back.