Angel banishing sigil

The angel banishing sigil, once drawn in human or angel blood and a hand pressed at its center, sends out a fierce light that banishes any angels within its blast radius. This sigil does no harm to the angels, it merely sends them to a different location on Earth, their vessels included. It also doesn't harm the vessels they occupy. This is, in a way, a weakness for the angels. Once the sigil is activated, the angel it is affecting temporarily loses access to its wings so that it cannot fly back to where he or she was banished from. They cannot stop it, once in use. It can be activated by both humans and angels (in human vessels); it does not banish the angel that activated it, unless the sigil was carved into his or her vessel's own flesh.

History
This spell was first demonstrated to the Winchester brothers by Anna in the season 4 episode Heaven and Hell. Dean later watched Castiel draw it on the wall in the Green Room to banish Zachariah. When Zachariah comes for him in the episode Sympathy for the Devil, Dean reveals to have drawn it on a sliding door and promptly sends Zachariah away using the sigil. He claims to have learned it from Castiel despite having first seen Anna use it. Following this, the Winchesters use it as an effective means of defending themselves against enemy angels, particularly in I Think I'm Gonna Like It Here and The Vessel when Dean is unable to defeat two enemy angels and Sam uses it to banish Lucifer. Metatron later attempts it on Amara to no effect in All in the Family. All angels are effected by the sigil including the archangels as demonstrated by Lucifer's banishment. In Lily Sunder Has Some Regrets, the angel Ishim reveals that a severely weakened angel banished by the sigil has a high chance of dying as a result rather than being banished to another location.

Another variation
In Caged Heat, Samuel Campbell drew a modified version of the sigil and activated it, banishing Castiel temporarily. The sigil was different than the "standard version" of angel banishing sigil used.

In All in the Family, Metatron used a modified version of the symbol on the Darkness. The main symbol had two circles on the edges, while the outside shapes were absent. When activated, the sigil had the same blasting of light effect, but was completely ineffective against the Darkness who was just amused by the attempt.

In Alpha and Omega, Lady Toni Bevell used a modified version of the symbol on Castiel. It has similar shape like previously Metatron used, but slightly tilted. When activated, the sigil had the same blasting of light effect and much faster. In Keep Calm and Carry On its shown that the sigil blasted Castiel into a field about three hours away from Lebanon, Kansas where it was used on him. This variation appears to have a lesser effect than the regular sigil as Castiel ended up only a few hours distance from where he was banished rather than thousands of miles away as he did in Two Minutes to Midnight and Reading Is Fundamental. This variation's only effect appears to be to blast the angel out of the location the sigil was used in as Castiel was not otherwise stunned by it nor were his powers effected.

In Lily Sunder Has Some Regrets, Dean drew a variation of the banishing sigil to banish Ishim. Dean's new banishing sigil, however, was very different than the standard version he commonly used. It appeared as a circle seal with three enochian glyphs. However, he doesn't use it when Ishim warned that in Castiel's weakened state, he might not survive a banishing.

Appearances

 * Season 4
 * Heaven and Hell  (by Anna, to banish Castiel and Uriel)
 * The Rapture  (by Castiel, to banish Zachariah's minions)
 * Lucifer Rising  (by Castiel, to banish Zachariah)
 * Season 5
 * Sympathy for the Devil  (by Dean, to banish Zachariah and his cohorts)
 * The Song Remains the Same  (by Sam, to banish Anna)
 * Point of No Return  (by Dean to banish Castiel and by Castiel to banish Zachariah's Guards and himself)
 * Season 6
 * The Third Man  (by Dean, to banish an unnamed angel)
 * Caged Heat  (by Samuel to banish Castiel)
 * Season 7
 * Reading Is Fundamental  (by Dean to banish Hester, her followers and Castiel)
 * Season 9
 * I Think I'm Gonna Like It Here (by Dean to banish two hostile angels, though the destination now might not be Heaven)
 * Heaven Can't Wait (failed attempt by Castiel to banish Ephraim) Metatron's banishing sigil.PNG
 * Season 11
 * The Vessel (by Sam to banish Lucifer)
 * All in the Family (used unsuccessfully on Amara by Metatron)
 * Alpha and Omega (by Lady Toni Bevell to banish Castiel)
 * Season 12
 * Keep Calm and Carry On (effects of Lady Toni Bevell's sigil and the used sigil)
 * Lily Sunder Has Some Regrets (by Dean to banish Ishim, unused)

Trivia
Engel-Verbannungssigille
 * Anna Milton was the first to show Sam and Dean this sigil. Ironically, they would later use it against Anna herself in The Song Remains the Same.
 * In some of the symbol's later appearances, the sigil had less intricate designs, but were shown to be just as effective.
 * So far they have used it at least once every season except seasons 8 and 10 since it was introduced.
 * Castiel is the angel who is most banished by the sigil including once while Lucifer was in control of his body.
 * Dean has used the sigil the most, having banished angels five times with it. Castiel uses it three times successfully and at least once unsuccessfully. It is unknown if he managed to use the sigil he drew in The Rapture successfully or not. Sam has only banished angels twice.
 * While Dean has banished more angels with the sigil, the two times Sam has banished an angel has been a significant angel enemy: Anna Milton and Lucifer.
 * The fact that Metatron used this to attack the Darkness indicates that the sigil may affect more than just angels.
 * In Keep Calm and Carry On, its shown that the sigil blasts the angel affected by it somewhere else on the planet where they appear in the form of a comet or meteor. This is also indicated in Two Minutes to Midnight and Reading Is Fundamental where Castiel ends up on a fishing boat in Louisiana and Perth, Australia respectively after being hit by a sigil.
 * Castiel has been banished by the sigil seven different times. Eight if Lucifer's banishment while possessing Castiel is counted.
 * The size of the sigil doesn't seem to affect the power of the spell since Sam used a smaller sized sigil to banish Lucifer who was the most powerful angel the sigil has ever been used to banish.