"Cardinal Rock" is the name of a famous band of travelling musicians.
Elroc, The Angry Bard was originally part of Cardinal Rock, most likely as one of the guitarists. Elroc was very jealous of the band's lead singer and after many disagreements between the two, Elroc was kicked out from the band. To this day, Elroc is still upset about the incident.
Any information about the other band members are not yet known.