One day, a girl named Stella Anderson wakes up in her home to find an angel-like spirit named Tueri, who tells her that she possesses KX, an energy-based elemental power that consists of many abilities. She also tells Stella that she also possesses a power called the Starlight, an extremely powerful spiritual power directly connected to the soul; however, it must be unlocked through various challenges.
Stella soon realises that an evil entity, known as Lord Tenebris, is invading and that she and three more select KX wielders are the only ones who can defeat him. She then sets out on a journey, meeting Hadyn Yeager, Mizusora Privette, and Leto Corrado along the way, to find her power and a sacred weapon so she and her comrades cam defeat Tenebris before he destroys the entire world and possibly even beyond it.
Starlight functions much like other action RPG games. The player travels a large overworld, filled with enemies, secrets, and items. The overworld contains lots of secrets (many of which are hard to find and contain rewards for discovering). While exploring, enemies are seen on the map but can be avoided. Although some are surprising, jumping out of nowhere, and sometimes the player has no choice but to fight them.
As the player fights and gains items, they gain XP to level up. The player can level up to Level 100, with rewards and new abilities able to be unlocked by reaching a certain level. The leveling-up process grows longer as the player gets stronger. Each character has their own seperate level, but the team as one has a Team Level that defines the strength of the entire team. This can be used to let the player know how powerful their team is. Accessing certain areas require characters to be leveled up to a certain amount.
|Stella Anderson||She may be a seemingly average girl at first glance, but Stella is a wielder of incredible KX abilites. From element manipulating to the legendary power of the Starlight, she is a force to be reckoned with. She is the main protagonist of the game.|
|Hadyn Yeager||A boy who has specializes in the art of Pyro KX. Hadyn has a short fuse, and it makes him a little hard to get along with. From fireballs to fire snakes, Hadyn isn't one you want to get angry.|
|A girl specialized in using Atmo KX and Hydro KX. She's a very calm and collected one, and spends much of her time outside admiring the breeze.|
|Leto Corrado||Having mastered mysterious ancient arts, Leto can create illusions (Mira KX) alongside his standard KX powers. He is a skilled user in KX, but he hasn't fully mastered his illusion abilities yet.|
|Tueri||An ancient spirit who acts as a guardian for Stella. She has impossibly vast knowledge about the world, and aids Stella and her comrades in their quest. She is the game's main assist character.|
|Lord Tenebris||An entity whose been alive for over a thousand years, Tenebris is a master in dark magic and a malevolent being. Having no disregard for life, he wishes to unleash chaos upon the world. He is the game's primary antagonist.|
|Luna||An entity that is a pure incarnation of Stella's negative emotions and feelings, Luna was created by Tenebris. She likes very much like Stella, and can easily be mistaken for her if you don't look close enough. She is one of Stella's primary threats throughout the game.|
- Many of the game's names include Latin and Japanese words/meanings. Some examples of this include Stella, which means "star" in Latin; as well as Mizusora, a combination of the Japanese characters 水 (mizu, meaning water) and 空 (sora, meaning sky).
- The game shares elements similar to the canon Earthbound/Mother series. Both are RPGs (though very different in what type) and feature characters with energy-based psychic/elemental abilities. Earthbound was in fact, one of the inspirations for STARLIGHT.