"Once Upon A Time" Season 3, Episode 20 ("Kansas") airs on ABC this Sunday, May 4. This week's new episode shows the birth of Snow White's second child. She and Prince Charming share one heart, literally, as revealed in the most recent answers. Watch the promo video for a big teaser: Evil Queen vs Wicked Witch - the big fight.

Spoiler alert: This feature contains major spoilers on Once Upon A Time Season 3. Episode 20, "Kansas," shows everyone, including the Evil Queen, rallying behind the Charmings. Read at your own risk.

Here are the most recent answers that Oncers have learned up to OUAT 3x19: Snow White (Ginnifer Goodwin) herself cast the dark curse that brought everyone back to Storybrooke. It was Baelfire aka Neal who sent Captain Hook (Colin O'Donaghue) to Emma Swan (Jennifer Morrison) in New York.

Snow crushed Prince Charming's (Josh Dallas) heart to enact the curse, believing only Emma could defeat Zelena the Wicked Witch. Snow later asked Regina to split her heart and share it with her true love. As of Once Upon A Time Season 3, Episode 20, all was well with the Charmings and Snow's stepmom.

The Wicked Witch (Rebecca Mader) erased a year of everyone's memory by "spicing up" Snow's dark curse. Emma Swan was hoping Henry wouldn't remember Storybrooke and their real life. But she realized Henry's belief in magic is crucial to the battle. When her adoptive son finally recognized her, Regina (Lana Parrilla) kissed Henry (Jared S. Gilmore) in OUAT 3x19. It was the true love's kiss needed to fix everyone else's memory.

In Once Upon A Time Season 3, Episode 20, the (formerly) Evil Queen risks her life once again to protect Snow White and her baby. Regina's soulmate Robin Hood (Sean Maguire) is the first line of defense. Oncers are looking forward to seeing how Dorothy Gale fits in the flashback story. In addition, Belle (Emilie de Ravin) and Rumplestiltskin aka The Dark One (Robert Carlyle) have a moment in this week's new episode.

Sunny Mabrey returns as Glinda of Oz. On TV.con, the OUAT 3x20 synopsis on TV. com states that "Glinda tries to convince Zelena to join the good witches as a protector of Oz." However, the Dorothy Gale incident made Oz matters worse.

WATCH: Once Upon A Time Season 3, Episode 20 Promo Video | ABC Clip on YouTube

Once Upon A Time Season 3 airs Sundays on ABC. The next new episode is called, "Snow Drifts." The OUAT Season 3 finale title is "There's No Place Like Home." Is the battle between evil and wicked ending ahead of the finale?

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