Metzen joins Blizzard as an artist and animator, initially working on games like Justice League Task Force and Blackthorne. This entry-level position marked the beginning of his long and impactful career at the company.

Worked as an animator for the game Justice League Task Force, creating animations for DC characters such as Superman.

Worked as an animator for the game Blackthorne, contributing his art skills to the platformer game.

Contributed to Warcraft: Orcs & Humans. Initially his contribution was not high but he still assisted with art.

Metzen takes on a more significant role in the Warcraft franchise with Warcraft II: Tides of Darkness, contributing to the game's story, character design, and world-building. This game establishes his growing importance within Blizzard.

Metzen helps shape the dark and gothic world of Diablo, contributing to the game's story and mythology. This marks his involvement in Blizzard's second major franchise.

Metzen is instrumental in creating the science fiction universe of StarCraft, serving as a writer, designer, and voice actor (voicing the Marine). StarCraft becomes a critical and commercial success, solidifying Metzen's status as a key figure in the gaming industry.

Continues his involvement with the Diablo franchise, expanding upon the lore and contributing to the story of Diablo II.

Metzen plays a central role in the development of Warcraft III, a game that significantly expands the Warcraft universe and lays the groundwork for World of Warcraft. He is deeply involved in the story, character design, and overall creative direction.