 At the conclusion of the first season, one of the show's animators confirmed that "Derpy" would be a scripted background character in the second season, and was a part of several sight gags. In the original broadcast of the mid-season episode "The Last Roundup" as well as on the home media The Friendship Express release, "Derpy" was called out by name by Rainbow Dash, and given lines (as voiced by St. Germain) and klutzy mannerisms as a direct call-out to the brony fandom. Though most of the fans appreciated the inclusion, some viewers had a negative response to the character, believing it insulted the mentally handicapped. Hasbro subsequently modified these scenes, and while "Derpy" is still present in subsequent broadcast and digital versions of the episode, she is not named, and a different voice is used. According to Hasbro's Nicole Agnello, "Some viewers felt that aspects of the episode 'The Last Roundup' did not stay true to the core message of friendship which is the heart and soul of the series. Hasbro Studios decided to make slight audio alterations to this single episode." Despite Hasbro's intentions, some members of the brony community were disappointed, and some made efforts to restore the original voice. "Derpy" remained in background cameos throughout other episodes in season 2 and 3. Within season 4, Derpy was re-introduced, remaining silent and unnamed but with her original wall-eyed look, as a side character in the main story of "Rainbow Falls". The appearance was planned as a big reveal for the brony fans, according to co-director Jim Miller, and that "she is here to stay" according to Hasbro's vice president for entertainment Mike Vogel. The Derpy character is used often on Hasbro's marketing of the show. For example, Hasbro's exclusive pony toy at the Comic-Con International and My Little Pony Fair in 2012 was based on "Derpy", and has the same cross-eye look.
