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.
For melodical elements I've used Keyzone Classic piano, BBC Symphony Orchestra flute, plucks from Serum and piano loop. Bassline is made from 1 layer of sub bass (Serum) and from 1 layer of bass guitar (Labs). Drums are made from one shots and percussions loop.
Sample pack Sample Magic - Raw Hip-Hop 2
Loop name RHH2_90_kit_loop_forces_piano_Gmin