This article is about a subject that is from official sources but is not considered canon.
After the Last Calusa is released upon Key West, the demon Fedra approaches hunter Dean Winchester with the idea of a using a gestalt ritual to defeat the spirit. Fedra's idea is to use the ritual to combine all of the spirits in Key West into Dean to give him the power to destroy the Last Calusa which is otherwise invulnerable and neither can defeat the Last Calusa alone. Though both are reluctant to work with each other, Dean ultimately agrees to the deal while having Bobby Singer stand by with the Colt in case Fedra tries something.
Possessing a young woman named Kat, Fedra performs the ritual upon Dean who uses the spiritual energy from the ghosts within him to attack the Last Calusa, gaining different effects depending on the emotion he uses behind his attacks. However, even empowered by the ritual the Last Calusa proves to be too strong for Dean to destroy. Eventually, Sam salts and burns some uncovered Calusa bones, destroying some of the spirits making up the Last Calusa and weakening it. While the Last Calusa is distracted repairing the damage to itself and thus vulnerable, Dean channels all of the spiritual energy given to him by the ritual into one blast and destroys the Last Calusa. However, Fedra is able to use the ritual to take control of Dean afterwards until she's exorcised by Sam.
The spell, being demonic magic, requires a reverse pentagram which the demon must sit within. The demon must slice open their palm and streak their blood on the cheeks of the person the spell is being used upon. The person the spell is being used upon must focus on something such as a happy memory to the exclusion of all else to ground them when the ghosts enter their body. Once the person is ready, the demon then chants the spell in an unknown language. After the spell begins, the ghosts will enter the targeted person who must use the thing they chose to ground them to gain control over themselves and all of the dead within them. Once they have control, they will have access to all of the spiritual energy belonging to the ghosts within them and depending on which emotion or instinct they choose to use, can direct that energy to different effects. The person the spell is used upon is also more vulnerable to emotional manipulation, especially if the spirits within them are highly affected by the emotion that is being manipulated within them.
During the ritual, the demon will be connected to the person the spell is cast upon through a line of spiritual energy no thicker than a fishing line. Prolonged use of the spell will burn out the demon's vessel, but once the spell is stopped, as long as its before the vessel dies, the burnout will disappear with no ill effects upon the vessel.
- According to Bobby Singer this type of ritual is high-level magic that monks could only pull off after fifty straight years of meditation. However, Dean states that a demon could do it easily.
- Fedra states that the ritual only works with a willing vessel for the spiritual energy.
- While under the influence of the ritual, Dean sees flashes of the lives of the spirits within him and they are able to communicate with him during his battle with the Last Calusa.
- Amongst the spirits combined upon Dean during the ritual are famous author Ernest Hemmingway and President of the United States Harry S. Truman.