The Big Man Upstairs was defeated by
Eileen Leahy - Sam's final love (Season 15)
Eileen Leahy (Shoshannah Stern) first showed up in Season 11's “Into The Mystic”, only to be killed a year later (“There's Something About Mary”).
After Castiel rescues Jack from a Grigori, the Winchester family is finally reunited. Jack explains that Billie kept him hidden in the Empty, waiting for God to leave to resurrect him. Jack has been following Billie's plan which, if he continues to follow it, will make Jack strong enough to kill God.
After going to Heaven, Dean is impressed and proud of the changes that Jack has made. Bobby Singer calls Jack Dean's kid while they talk and Dean doesn't say anything to the contrary, suggesting that Dean ultimately forgave Jack and came to see the young Nephilim as his family again.
Jack dies of his condition, leaving the Winchesters and Castiel in mourning. In an attempt to save Jack, Sam contacts angel expert Lily Sunder, now an old woman, who suggests that they can resurrect Jack and cure him with her magic which will use the power of Jack's own soul to sustain him.
Jack says he snapped and it was over quickly. He wishes it didn't happen. Dean is barely holding it together. He doesn't like that Jack is calling Mary's death, “the accident.” But he plays along and says they understand and they forgive Jack.
Supernatural 15x13 - Jack gets his soul back and says sorry to Sam and Dean for killing Mary!
After the second death of Lucifer and the betrayal and death of Michael, Jack absorbs God's power and becomes the new God, the effort to turn him into a cosmic bomb having also made Jack a power vacuum that sucked up all of the power around him, including from the fights with Michael, Lucifer and Chuck.
Though he was resurrected a second time with no soul, Jack's soul was subsequently restored by the Garden of Eden after he journeyed to it through the Occultum. Lily Sunder agrees to help resurrect Jack using her magic, but tells Sam, Dean, and Castiel that it will use part of his soul in process.
After a soulless Jack kills Nick for trying to resurrect Lucifer, he accidentally kills Mary in a brief fit of rage. Mary is reunited with her husband in Heaven and is now at peace in a shared Heaven with John.
Cassandra Masters is the daughter of Castiel and Meg Masters and the only known Nephalem to exist, which is a hybrid between a union of an angel and demon, even being part human due of Castiel and Meg's human vessels. Cassandra acts as one of the leading main characters with Sam and Dean.
Character Information
Jack Kline (b. May 18, 2017) is the son of Lucifer and Kelly Kline. He is the first and only known Nephilim to be sired by an Archangel. Jack was taken in by Sam and Dean Winchester who would teach him how to master his powers.
Billie resurrected Jack and sent him to Earth to feed on Grigori hearts in an effort to make him stronger so that eventually he'll be able to fight Chuck.
This one is a bit of a doozy, but the answer is yes. Dean accidentally conceived a child with Lydia, an Amazon who had a one-night stand with the Winchester brother in order to have a child. The child, Emma, was born two days after conception and grows up ridiculously fast.
Ben Braeden | Supernatural Wiki | Fandom.
In Supernatural's series finale, Dean Winchester died on a hunting job, but his soul eventually ended in Heaven. Some fans were happy to see a proper conclusion for Dean Winchester's story, while others argued that he deserved better.
In The End, Jack Became A “Hands-Off” Deity
He was more powerful than God and Amara together. He put the whole world to rights but didn't bring back all the people that had died because of his plan.
When Sam came back from Lucifer's Cage his soul was left behind which left him completely emotionless. Castiel sticks his right arm into Sam's chest and reveals to Dean that, the reason for Sam's cold/relentless behavior is because his soul is missing because of him being in hell.
Why is Jack stronger than God? After his survival of the initial explosion in the Empty and becoming a power vacuum that had absorbed enough energy, Jack became immune to God's and Amara's powers, best seen when God failed to smite him, Jack was then capable of absorbing all of God's powers.
In a final act of defiance, the Winchesters wouldn't submit to God himself. And while he beat them up … Jack won the war. You see, when Jack exploded last week, he apparently became a sort of a black hole absorbing power and energy, and as God used his power on Sam and Dean, Jack sucked it all up and … became God.
Some background: Jack, played by Alexander Calvert, is a Nephilim: a half-archangel, half-human hybrid with unprecedented sacred powers. His mother, Kathy Kline, became pregnant when she had an affair with the president of the United States while he was possessed by Lucifer, and subsequently died during childbirth.
After obliterating his rival, Raphael, Castiel took charge over Heaven and commanded all his siblings and his human friends to recognize him as the "New God".
Jack's descent into evil arguably began as soon as his power was restored, as, immediately after Michael's defeat, Sam, Dean, and Castiel looked noticeably frightened at the youngster's ominous power.
In Ouroboros, Jack absorbed the Alternate Michael's grace returning him to full power, although he had to burn off his entire soul in order to kill him. When his powers were restored, Jack displayed his full angelic wings to show he was himself once more.
Castiel: Resurrected three times by God and once by Gadreel. He was resurrected another time by the Shadow and later by Jack.