Guest Stars James Blendick voices Galactus Camilla Scott voices Shalla-Bal Marc Strange voices Lord Glenn Aron Tager voices Master of Zenn-La Gary Krawford voices Thanos Credit Only Jennifer Dale voices Various Cedric Smith voices Various Alison Sealy-Smith voices Various Colin Fox voices Various Norm Spencer voices Various Robert Bockstael voices Various Tara Rosling voices Various Elizabeth Shepherd voices Various John Neville voices Various Uncredited Denis Akiyama voices Watcher Valerie Buhagiar voices Shellaine John Stocker voices Ivar Roy Lewis voices Ego the Living Planet Alyson Court voices Amber