The base is original from the producer (chords and melodies), but is complemented with elements that complement the song that come from samplepacks, usually, vocal chops, guitars, wobbles sections, glitch effects. It is the standard in which most of producers work, in a project you will find MIDI files made by the producer, but also melodic loops.
Emotional and cinematic chords, piano layers with strings to create tension. Orchestral drums to build energy and hype for the drop. The drop consists to huge and thick saws, combined with heavy hitting drums, fills and glitch effects, thick baseline and giant war horns to make the whole drop massive.
Sample pack Cinematic Sounds - Valhalla Choirs
Loop name CS2_140_Songstarter_02_Valhalla_Choir_Am