Complex sentence: In Athens, he played occasional guitar with punk favorites Bar-B-Que Killers, later forming his own group, Mercyland in 1985, in which he was the main songwriter, bassist, and co-lead singer.
Split into simpler sentences: In Athens, he played occasional guitar with punk favorites Bar-B-Que Killers. He later formed his own group, Mercyland in 1985 and acted as the main songwriter, bassist, and co-lead singer.