Grants a 50% Buster buff for 1 turn (level second).
A younger, comical "Santa" version exists, known as Santa Alter Lily.
Boosts critical damage (+50%) and star gathering rate for 3 turns (ideal to level first).
Here is a helpful summary of her character and usage in FGO:
Born from a wish upon the Holy Grail by Gilles de Rais, she represents a twisted version of Jeanne d'Arc seeking revenge. Over time, she develops into her own person rather than just an imitation of her saintly self.
She is a heavily featured character in fan art, merchandise, and cosplays.
Based on the search results, "Joan Alter" (often referred to as or Jalter ) is a popular character from the Fate/Grand Order (FGO) mobile game and anime franchise. She is a distorted, "Altered" version of the historical Joan of Arc, appearing as an Avenger-class servant designed to be a vengeful figure.
A party-wide damage boost that doubles for [Dragon] trait allies (level last).
