Anthropomorphic Design: She has the appearance of a girl approximately 8 or 9 years old with flawless synthetic skin and expressive blue eyes. 

Acid Humor and Sarcasm: M3GAN has developed a much more pronounced sense of humor. It frequently makes ironic comments about human frailty or the "inferiority" of other artificial intelligences.

Alpha ego: She is extremely competitive and proud. She cannot tolerate the existence of Amelia, whom she considers a cheap and defective imitation of her own.