In 2010, Dark Horse Comics published all three translated volumes as one volume.

userscloud.com/9bechs8cyf67/Blacksad (2010) (digital) (Son of Ultron II-Empire).cbr
userscloud.com/rz778629zkta/Blacksad – A Silent Hell (2012) (digital) (Son of Ultron-Empire).cbr
userscloud.com/sabxmeeq4efu/Blacksad – Amarillo (2014) (digital) (Son of Ultron-Empire).cbr