Eternal Cadence

 is an American adventure-fantasy rhythmic RPG video game series created by TBD, being published by Disney Interactive Studios (from 2001 until 20??) and Warner Bros. Interactive Entertainment (under license from The Walt Disney Company, since 20??) since August 17th, 2001.

Synopsis
The series explores several worlds and tones that primarily involve fantasy and built around music. Each game features both a musical-based plot relevant detail and a white-haired character named Cassandra.

Eternal Cadence
Set in the kingdom of Asperion, a young knight-in-training known as Kai discovers a guitar-like blade known as the Rhythm Buster as he quickly gets thrown in a quest to save the kingdom when the king gets captured by the forces of the seemingly aggressive and villainous kingdom of Tyriox.

Eternal Cadence II
Set in the realm of Aglaria, Cassandra Phallax is a young teenager who has awakened powers tied to an ancient dragon known as the Black Melody as she enrolls into the Audaire Magical Academy, soon learning of something sinister tied to the academy and her dragon magic when students start to vanish.

Eternal Cadence III
Set in a world where everything drowned known as Kalistar, a young dock worker discovers an ancient violin-like blade as he gets thrust between a war between two warring sides: the regime known as the Iron Authority and a resistance group, as he tries to find a way to stick up against the Iron Might.

Eternal Cadence Strive
In the realm of ltia, monsters have spread over the realm as a monster slayers organization is formed as a new recruit learns of a mysterious conspiracy involving enraging monsters using a mysterious song.

Games

 * 1) Eternal Cadence (2001)
 * 2) Eternal Cadence II (2004)
 * 3) Eternal Cadence III (2007)
 * 4) Eternal Cadence Strive (2011)

Introduced in Eternal Cadence

 * Kai (voiced by TBD) - a kind-hearted and brave knight in training who discovers the Rhythm Buster blade and gets thrust in a quest to save King Lionel from the Tyriox Kingdom, making both new friends and enemies.
 * Cassandra (voiced by TBD) - a cocky fellow knight who is Kai's superior as she joins him on his quest to save the king, both growing a crush on him and uses her shield to be far more defensive than Kai.
 * Hector (voiced by [aging]) - a goofy old hermit who actually happens to be a skilled mage as he joins Kai's team as a mentor and as an experienced music-mage.
 * Princess Maria (voiced by TBD) - the rebellious and fun-loving princess of Tyriox who has ran away from home, wanting to find adventure and ends up being convinced by Kai to join his band of adventurers.
 * Sparrow (voiced by TBD) - a mysterious yet honorable thief who was forced into a life of crime as he ends up being found by Kai as he decides to join them, due to blaming Lionel for his position.

Introduced in Eternal Cadence II

 * Cassandra Phallax (voiced by TBD) - an eager teenager who learns she is powered by magic tied to the ancients Black Melody dragon as she enrolls into the Audaire Academy, quickly learning something sinister is happening.
 * Jack O'Hair (voiced by TBD) - a prefect who is assigned to guide Cassandra through the academy as his magic suddenly starts acting up, joining Cassandra, feeling she could help him figure out what is going on.
 * Eliza Vanadis (voiced by TBD) - a somewhat bitchy student at the Audaire Academy who heads the Hex Ball team as she is soon forced into joining Cassandra after she saved her from a [monster], slowly starting to grow on her.
 * TBD

Introduced in Eternal Cadence III

 * Samuel Prantice (voiced by TBD) - a noble but single-minded dock worker who finds an ancient violin-like blade, getting thrust into a battle against the Iron Authority.
 * Nina Lockley (voiced by TBD) - a giddy and super kind mechanic who works for the resistance as she encounters Samuel and convinces him to join the fight.
 * [mentor-like]

Introduced in Eternal Cadence Strive

 * Cassandra Primrose (voiced by TBD) - TBD

Introduced in Eternal Cadence

 * Queen Selena (voiced by TBD) - the seemingly malicious Queen of Tyriox who has begun a full-fledged invasion of Asperion. It is revealed that she was initially corrupted by the Nemesis to continue the cycle of war between the kingdoms before breaking free, prompting her to kidnap King Lionel due to learning of his connection to Nemesis, believing he may hold a key to defeating him.
 * Arthur (voiced by TBD) - a friendly and joyous man who is a shopkeeper, running a shop in Asperion and helping Kai and the gang, often selling random items.

Introduced in Eternal Cadence II

 * [incriminated headmistress] (voiced by TBD) - TBD

Introduced in Eternal Cadence

 * The Nemesis (voiced by Kevin Michael Richardson) - a dark entity who represents the darkness and evilness in the hearts of man as he has corrupted the rulers of both kingdoms to be in a perpetual war as he enjoys the chaos and destruction that he causes.
 * King Lionel (voiced by TBD) - the seemingly benevolent king of Asperion who was kidnapped by the forces of Tyriox. It is revealed that he is a worshipper of Nemesis and has willingly been continuing the cycle of war and death, wanting to serve by Nemesis' side when he becomes god.

Introduced in Eternal Cadence II

 * Prometheus/Preston Pallock (voiced by TBD) - a teacher at the academy who is revealed to be Prometheus, the master of the Black Melody, as he has been kidnapping students to try and unlock Cassandra's potential as the Black Melody's reincarnation so he may enslave her and use her as weapon of destruction.

Introduced in Eternal Cadence III

 * The Iron Authority, consisting of:
 * Divine Emperor Albert Kincaid (voiced by TBD) - the extremely flamboyant young recently elected Divine Emperor of the Iron Authority who wants to conquer the rest of Kalistar, both enslaving villages and trying to uncover ancient artifacts left by the precursor race, being interested by Samuel.
 * Cassandra Malden (voiced by TBD) - a terrifying and cold commander of the Iron Authority who learns of Samuel and his connection to the resistance as she wants to force him to join the Iron Authority.

Introduced in Eternal Cadence Strive

 * The Lady (also voiced by TBD as "Cassandra" and voiced by TBD in true form) - a mysterious shapeshifting entity who is out to take control of all monsters, being responsible for creating the song that enrages monsters as she ends up taking the form of Cassandra due to being fascinated by her.

Recurring

 * Goblins - a chaos-loving species that enjoys pillaging innocents and causing destruction and mayhem, being common starting enemies.
 * Trolls - aggressive and hulking creatures who want to attack whoever they want out of pure territorial instinct, some of them carrying massive drums on their backs.
 * Orks - slightly weak yet intelligent specimen who evolved from goblins as they are notably stronger than them but are mainly dangerous due to being able to plan.

Gameplay
The games play as a turn-based RPG as you explore through the region, battling against enemies. The combat is rhythm based as every attack requires you to press buttons at the correct rhythm or else the attacks will cause less damage. Special attacks require MP (music points) and more fast and difficult button presses yet causes way more damage. The games have a leveling system as after leveling up your characters gain more health and attack points. The games also have shops where you can buy items to heal and boost stats.