Buttercup is the green-themed member of the Powerpuff Girls in the original series.
Buttercup is the third member of the trio alongside Blossom and Bubbles. Her design uses a green dress and black hair, making her visually distinct from Blossom’s pink-associated appearance and Bubbles’ blue-associated appearance.
She is commonly portrayed as the toughest and most impulsive of the three sisters. Buttercup enjoys fighting villains and often approaches problems more directly than Blossom, who tends to lead, or Bubbles, who is usually gentler and more playful.
Color associations are useful for identifying the characters, but they are not the source of their powers. All three girls are created through the same laboratory experiment and share a broad set of superhuman abilities.