Annunziata joined Sega in the early 1990s, where he was the lead designer on Ecco the Dolphin (1993). The game departed from typical Genesis games by featuring a sentient dolphin protagonist on a quest to reunite with his pod after an alien abduction.[1]
Later he served as an executive producer for Nokia's N-Gage mobile phone and gaming device, helping create nearly a dozen multiplayer titles for the platform. One of them, Smallball Baseball, was one of the first microtransactions-based games targeting the US market.[2] In 2006, he founded Twofish, Inc. (now part of Live Gamer) with Lee Crawford and Sean Ryan.