David Vonderhaar, also known as Vahn, (born September 8, 1972) is an American video game developer and game designer. He is best known for his work on the Call of Duty Black Ops franchise.
Vonderhaar joined Activision to become a quality assurance tester, web designer, and online manager for several titles. In 2006, he led the design of Call of Duty 3 and several other Call of Duty games developed by Treyarch. He designed the multiplayer systems for ' and ', along with the campaign, multiplayer, and free run modes for '.
Vonderhaar led the design systems for the campaign and multiplayer experiences of ', before transitioning to full-time development on Blackout after the campaign mode was cancelled. He also worked on the multiplayer of ' and its Fireteam modes.
On August 18, 2023, Vonderhaar announced that he had left Treyarch, after eighteen years. He established NetEase's company BulletFarm.
Vonderhaar has a competitive-focused agenda and is inspired by Esports gameplay design. Vonderhaar has spoken on the development of League Play, a competitive mode introduced in ', and their goal to make Treyarch games "fun to play, and fun to watch". Starting with ', Vonderhaar worked closely with competitive players and Esports professionals to improve the spectating and gameplay experience of Call of Duty.