The answer is: "OST song" refers to the song in the OST. OST referred to the original music in movies, TV series, and other film and television works, and the song part was the OST song. According to the search results, some OSTs of movies and television works included some songs, such as the theme song of the TV series OST of " A Thought of Passing Mountains," many of Zhou Shen's OST songs, and Yu Kewei's Top Ten Classic OSTs. Therefore, an OST song referred to the song part of the original music in a film or television work.
The OST lineup for the second season of Celebrating Years had already been announced. Among them, Li Jian sang the theme song " In My Lifetime," Zhou Shen sang the ending song " Excuse me," Liang Long, Liu Duanduan, Zhang Haowei, and Guo Zifan performed the promotional song " Aiya." These songs would bring more musical elements to the second season of " Celebrating Years," adding more emotions and atmosphere to the plot.
Ender Wiggin is the most important character. He's a brilliant and complex boy chosen for Battle School to train to fight the Buggers. Valentine, his sister, is also important. She has a deep connection with Ender and represents a more empathetic side. Colonel Graff is a key figure too. He's in charge of Ender's training and often makes difficult decisions regarding Ender.
The main themes include survival. In the harsh environment of Battle School and the threat of the Buggers, characters have to fight to survive. There's also the theme of manipulation. The adults in the story manipulate the children, especially Ender, for their own ends in the war against the Buggers. And the theme of identity. Ender struggles with who he really is as he's shaped by the military training.
One common theme is the exploration of Ender's character further. Writers often want to dig deeper into his psyche, like his guilt and how he copes with it. Another theme is alternate universes. They create different scenarios for Ender, such as if he had made different choices during the battles. Friendship is also a theme, showing his relationships with other characters in new lights.
In 'Enders Game', Mazer Rackham's story is crucial. He was the hero who defeated the Formics in a previous invasion. His victory became a legend and a strategic model. Ender was later trained based on Rackham's experiences.
The theme of leadership is prominent. Ender has to lead in difficult situations, making tough decisions. Also, the idea of identity is there. Ender struggles to define himself as a person outside of the military expectations placed on him.
Ender is the most important character. He is a brilliant child who is chosen for military training. His sister Valentine also plays a significant role. She is a source of kindness and normalcy in Ender's life.
OST was the shortened form of original music, which referred to the music used in movies, TV series, games, and other media works. It included scores or songs from movies, as well as music from anime. OST was usually released in the form of an album for the audience to enjoy. It could be released as an independent piece of music and receive independent attention and recognition.