Guest Stars Steve Alterman voices Additional Voices Mitch Carter voices Additional Voices Nolan North voices Stoick Haddock Chris Edgerly voices Gobber Alfred Molina voices Viggo Grimborn Hakeem Kae-Kazim voices Krogan Alastair Duncan voices Additional Voices David Tennant voices Spitelout Jorgenson Adelaide Kane voices Mala James Arnold Taylor voices Throk Lucas Grabeel voices Gustav Larsen Edie Mirman voices Additional Voices Peter Lavin voices Additional Voices Jeff Bennett voices Additional Voices Hakeem Kae-Kazim voices Drago Wendy Cutler voices Additional Voices Jeff Bennett voices Flyer Leader