Jason Avent, the head and co-founder of CSR Racing creator Boss Alien, has left the company.
Avent confirmed the news via his Facebook page, having previously posted a picture of the office clad in leaving decorations (via GI).
No reason was given regarding his departure.
Formed in 2011 by former Black Rock Studio devs including Avent, Boss Alien was picked up by NaturalMotion just a year later, before transferring to Zynga when Natural Motion was itself purchased in 2014.
Its first game, CSR Racing, was released in 2012, followed by CSR Classics in 2013.