Co-creators Michael Dante DiMartino and Bryan Konietzko wrote the majority of the finale; DiMartino wrote parts one, three, and four, and Konietzko assisted with parts three and four. Aaron Ehasz, a frequent writer for the series, wrote part two. Ethan Spaulding directed part one (The Phoenix King), Giancarlo Volpe directed part two (The Old Masters), and Joaquim Dos Santos directed parts three and four (Into the Inferno + Avatar Aang). Dos Santos was nominated for an Annie Award for his directing of part three, "Into the Inferno". Although "Sozin's Comet" was originally written as a three-part story, the creators noticed that the length had grown beyond what they had predicted from the initial script. To avoid pacing issues, they split the final part in two, adding several scenes to fill the remaining time.