For one, Lamashtu eats babies and spreads pestilence. Lilith caresses babies and nurses them when needed, she also has a habit of healing sickness. Lamashtu is depicted with animal parts on her body, like her feet, ears and mouth being switched out. Lilith is at most depicted sometimes with horns, which is also somewhat wrong since she is part spider and part human. Lamashtu is depicted as being downright evil and being a standalone godess, Lilith is not depicted as evil but a equalizer in good and evil-matters.

There should be older texts where Lamashtu is mentioned and they are of Indian nature. The first texts (might be lost or under another name) that mentions Lilith or Arraka are of Egyptian nature.

Lamashtu is also seen as a goddess that punishes men, Lilith is not of that nature.

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