The two best known keyboard pieces by Kerll are both programmatic, descriptive pieces. "Battaglia" is a descriptive piece in C major, over 200 bars long and featuring numerous repeats of fanfare-like themes, it is also attributed to Juan Bautista Cabanilles. "Capriccio sopra il Cucu" is based on an imitation of the cuckoo's call, which is heard more than 200 times in the piece. It is modelled after Frescobaldi's piece based on the same idea, "Capriccio sopra il cucho", but is more structurally and harmonically complex. The idea of repeating a particular theme in Kerll's music reaches its extreme in the "Magnificat tertii toni", where a fugue subject consists of sixteen repeated E's.