Already having dropped troubled bassist Michael Todd from the lineup, Coheed and Cambria say farewell to the other half of the rhythm section as drummer Chris Pennie leaves citing "creative differences."

It can't be easy to be in a highly conceptual art rock band, and as we've been learning -- it's not. Coheed and Cambria has had more than their share of growing pains over the last year -- the first of which being the arrest of bassist Michael Todd in Boston prior to the band's opening slot for Soundgarden. Todd's struggle with addiction had become such an issue that it fueled him to rob a pharmacy just hours prior to the gig.

Now, just as the band was getting underway with the recording of their next album, they will face the ever-difficult task of replacing another member. Drummer Chris Pennie announced via Facebook that he was leaving the band yesterday, with both the band and Pennie saying the split is caused by "creative differences." Pennie plans to continue work with his progressive metal outfit Return to Earth, which he made light of in his Facebook statement:

"I am very thankful for the years that I shared the stage with the guys and want to thank the amazing, supportive fans that I've met while on tour, but there are a lot of exciting projects on the horizon, in addition to RTE and Fight Mannequins, that I feel require my absolute 100 percent commitment and attention. I feel that this is the right time to make that happen."

Pennie joined Coheed and Cambria in 2007, replacing their drummer at the time Josh Eppard. Pennie has since toured extensively with the band and appears on the band's last album -- 2009's 'Year of the Black Rainbow.'