|Although this article is based on canonical information, the actual name of this subject is conjectural.|
- “Kali, Hera, Kronos, Thonic. Air like nectar thick as onyx. Cassiel by your second star, hold mine victim as in tar.”
- ―Willow Rosenberg[src]
This spell was a powerful incantation that invoked a number of gods and spirits. It was meant to contain someone turning the air around them as thick as tar. This spell was found by Willow Rosenberg in a tome named the Darkest Magick in Giles's off-limits stache in The Magic Box. Willow used the spell in a battle against Glory. Apparently it was strong enough to hold even the hell-goddess.
The spell involved calling upon the gods Kali, Hera, Kronos, Thonic and Cassiel. The spell could be reactivated later on by the witch without the need to reinvoke the gods, instead needing only to say 'thicken', and even later, with only a gesture of the hand. It is unknown how long the spell held before the witch had to recite the invocation again.