Seraphina

Seraphina is a character on the ABC series Once Upon a Time. She first appears in "The Eighth Witch".

Before the First Curse
Seraphina is born with magic, however, she keeps this a secret from everyone else, fearing she will be hunted down. One day, while Seraphina, Isla and their friends are trying on dresses, Gothel, a tree nymph, causes a flower on one of the dresses to bloom. When they re-enter the room, Isla and Seraphina insist that they are fine with her having magic and invite her to a ball tonight; she agrees to come and teach them magic.

That evening, Isla takes Seraphina, Gothel and the others to an abandoned greenhouse, as Seraphina worries about the consequences of what will happen if Gothel uses her magic in public. When Gothel magically makes a flower grow, Isla betrays her by smashing the flower and having the others pin Gothel as she dumps mud on her. After taunting Gothel, Isla leaves with the others, though Seraphina sadly looks at Gothel, reminded of herself, before following the others.

After finding out Isla and other humans killed all of the tree nymphs except her, Gothel returns to the ball to kill Isla. Not taking Gothel seriously, Isla attempts to have two guards capture her, only for her to impale them with roots. As Isla and Seraphina back away from Gothel in fear, the guests attempt to flee, only for Gothel to lock the door with roots. She then uses them to tie Isla up and, as Isla begs her to stop, kills her. Seraphina rushes over to Isla's dead body, and when Gothel attempts to kill her too, she blocks the attack, revealing that she had been keeping her magic a secret to protect herself as she feared being targeted. Gothel tells her to join her so that she can finally be herself without fear of people targeting her and Seraphina agrees. Realizing more guards are arriving, Seraphina suggests that they flee, but Gothel brings plants through the fireplace to expel poisonous spores into the castle, killing all the remaining humans at the ball.

Later, seeing the remanents of Gothel's destroyed grove, Seraphina apologizes for what happened and Gothel states that as the tree nymphs are now dead, the humans have created the first land without magic in existence. However, Gothel knows that humanity will find a way to return eventually, and when that happens, she swears to exact revenge upon them. Gothel then finds a magic bean among the rubble and uses it to open a portal to a new land, where she and Seraphina can use magic. Seraphina follows her into this other world and the two eventually reach the Magical Forest.

After the Fourth Curse
When Gothel forms the Coven of the Eight, Seraphina becomes the first recruit, alongside four other witches. Together, their combined power allows them to perform feats of magic, any singular witch is incapable of. Leota, along with the other members, come to Tiana's Palace, to free Drizella, from her petrified stone state, she was placed in, eight years prior, before disappearing, with plans to cast the Dark Curse. The coven later capture Henry, who was attempting to escape the curse with his daughter, and have him poisoned, as a means of forcing Regina, into using her blood. Acting as the final ingredient, Leota and the coven, successfully enact the curse, and the entirety of the coven, are sent to Hyperion Heights, with new cursed personas.

During the Fifth Curse
After being transported to Hyperion Heights, Seraphina takes on a new identity, with no memory of her past life. Eventually, her memories are restored by the Desk Sergeant under Gothel's orders, and she and the rest of the Coven set up a trap for Rogers and Tilly, capturing them at the basement of a movie theater where Gothel's Grove once stood. After receiving some encouragement from Seraphina, Tilly is then forced to help her mother, Gothel, cast a spell that will exterminate all of humanity or Rogers will die.

Trivia

 * Aside from Hades, Zeus, Gothel and possibly the Black Fairy and Merlin, Seraphina is the oldest known character in the series.