Character: Morgan

Morgan le Fay is the sister of King Arthur and mother of Mordred.

Morgan was born as the proper, recognized daughter of King Uther. Although the older sister and of the same status, Arturia received the love and hopes of their father in Morgan's eyes, driving her to eventually become a witch queen who craved for vengeance for the rest of her days. During Arturia's training, Morgan executed a trap, and due to Merlin's womanizing, Arturia was caught up in it and lost Caliburn. Once Camelot was built, she went into seclusion. She sent Agravain as an assassin. She was a fairy of the lake and the evil polar opposite of Vivian, the Lady of the Lake.

She eventually enchanted Arturia, a pseudo-male at the time due to Merlin's intervention to produce an heir, and extracted sperm from Arturia to develop as a homunculus clone within her ovary. Mordred was soon born and aged rapidly, and Morgan raised her in secret while telling her of her right to the throne. She told Mordred to never remove her helmet and recommended her to the Round Table. She directed Mordred to hide her status and obey the King until she could defeat Arturia and take her place. While Mordred was initially idealistic and served as a proper knight, Morgan shattered her innocence with the truth of her birth to guide her towards the path of rebellion.

Source: TYPE-MOON Wiki