The music playing at the beginning of the episode (when Pablo Escobar sings along in the shower) and at the end is the tango "Cambalache". The lyrics are about the decline of society at the time it was written in the 1930s.
The game Pablo Escobar and his son are playing is "Streets of Rage" (a.k.a. Bare Knuckle) on the console Sega Genesis (a.k.a. Mega Drive).
The version of the song "Cambalache", a tango which is featured in the opening, was sung by Julio Sosa, a Uruguayan singer known as "El varón del tango", or "The stud of tango".
The title "Cambalache" translates to "Pawn Shop" in English, when translated from "lunfardo", the 30's era slang commonly used in Uruguay and Argentina.