Alter - Joan

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).

She is best used in teams that can provide critical stars to maximize her high critical damage potential. Jeanne d'Arc Alter | TYPE-MOON Wiki | Fandom Joan Alter

She is a heavily featured character in fan art, merchandise, and cosplays.

A party-wide damage boost that doubles for [Dragon] trait allies (level last). A younger, comical "Santa" version exists, known as

Here is a helpful summary of her character and usage in FGO:

As an Avenger, she is a high-damage dealer, often noted for having some of the highest Attack (ATK) values in the game. Key Skills (Leveling Priority): Jeanne d'Arc Alter | TYPE-MOON Wiki | Fandom

Grants a 50% Buster buff for 1 turn (level second).