Complex sentence: The mascots featured in an Olympic-themed comic strip in "The Beano" issue 3601, and the strip, drawn by Nigel Parkinson and written by Ryan C. Gavan, ran up until the Olympics began in July 2012.
Split into simpler sentences: The mascots featured in an Olympic-themed comic strip in "The Beano", starting in issue 3601. The strip, written by Ryan C. Gavan and drawn by Nigel Parkinson, ran until the Olympics began in July 2012.