God

"No doubt, endings are hard. But then, nothing ever really ends, does it?"

God, also called the Creator, the Lord, or the Man Upstairs, is best known as the creator of the entire Universe. God is, by far, the most revered and powerful god (as his archangels are more powerful than the other gods) in history and is worshiped above all the other gods. Some of his best-known creations include the archangels (Michael, Lucifer, Gabriel, and Raphael) and the angels beneath them. He is the creator of both the Earth, humanity, and all of creation. At the end of time, he too will be supposedly reaped by Death. This is not confirmed though and details about it have not either.

Early History
In the beginning, God alongside Death existed. He then created Heaven as a dwelling place where he and his angels will reside. He then created four Archangels named Michael, Lucifer, Raphael and Gabriel. He then created Angels and Cupids. The Angels and Archangels called God their father and existed only to glorify him.

Soon, God created humans. He then asked all the Angels to bow down to the humans as his greatest creations. Lucifer soon became envious, as he was the favorite son of Heaven, and saw that humans were flawed and murderous. This soon led to Lucifer becoming more and more prideful. He convinced one-third of all of Heavens Host to rebel with him. Soon before, Lucifer went to Michael and asked him to stand with him, but Michael refused. A great and bloody battle then ensued in Heaven where Angel warred against Angel. Michael and Lucifer fought in a cataclysmic battle until eventually, God caused the battle to cease by casting all the rebels, including Lucifer, out of Heaven.

After Lucifer corrupted Adam and Eve, God had Michael cast him into Hell. God then continued to watch over and protect all his creation and children against anything that might hope to corrupt it.

Season 5
In "Sympathy for the Devil", Dean and Sam are trapped while Lucifer is about to emerge from his cage. Eventually, everything becomes bright and the brothers find themselves on an air plane. They were put there by none other than God, Himself. Later, when Dean questions Sam on how he's feeling, Sam notes that it's weird because he's not shaking and doesn't have a fever like he normally does after drinking demon blood. Sam gives the credit to whoever saved them and put them on the plane. It is also speculated that Chuck Shurley is, in fact, God due to the fact that at the end of the season five finale, "Swan Song", Chuck evaporates after stating: "Nothing really ends"

Powers & Abilities
Omnipresence: God exists everywhere in the universe as he is one of the two fundamental forces in it the other being Death

Omniscience: God is said to have unlimited knowledge and understanding and awareness of the universe.

Omnipotence: God is confirmed to be the most powerful being in the universe but it is not known if he is more powerful than Death.

Immortality: God is older then time and possible older though he and Death don't remember who is older. In turn of immortality, he is also invulnerable to all kinds of harm whatsoever.