The Great Ritual was a ceremony practiced on rare occasions amongst the Tarasin of Cularin. When the entire Tarasin civilization was threatened the Ritual, which involved a call to all irstat leaders to come together to discuss the fate of the Tarasin. Until the threat had passed, the Ritual would not break, thereby promising the survival of the race.
During the Clone Wars, the last known Great Ritual was called by Mother Dariana of the Hiironi irstat. The Ritual was proven well called for when the Cularin system was placed under martial law, and the Tarasin were forced to flee the planet.
Appearances
"Hearts of Green and Gold" (original article link) on Wizards.com (content now obsolete; backup link) (Mentioned only)