Complex sentence: Under his tenure, the Adult Swim block was created and launched and numerous original series premiered, & went to resign the week after 2007 Boston bomb scare, which resulted in Stuart Snyder taking over his position as Cartoon Network's manager as soon as he left.
Split into simpler sentences: Under his tenure, the Adult Swim block was created and launched and numerous original series premiered. He went to resign the week after 2007 Boston bomb scare, which resulted in Stuart Snyder taking over his position as Cartoon Network's manager as soon as he left.