Complex sentence: Metzen is currently the vice president of creative development at Blizzard Entertainment and has assisted the company's projects by providing voice talent for a number of characters, as well as contributing to artistic character design.
Split into simpler sentences: Metzen is currently the vice president of creative development at the company. In addition, Metzen has assisted Blizzard Entertainment's projects by providing voice talent for a number of characters, as well as contributing to artistic character design.