The Clan believed that Ursus had taught them to live in caves, wear furs, and rest during the winter on summer's food. The purpose of the bear's captivity was to show Ursus that the Clan still followed his ways.
On the day of the Bear Ceremony, the people ate only a breakfast of bland biscuits and fasted until the ceremony. A man was selected from each of the three highest-ranking clans to participate in the ceremony; this was a special honor. The lower-ranking clans then selected three of their best hunters for the ceremony.
During the ceremony, the mog-urs wore bear skins and painted their faces black with manganese dioxide. The three hunters chosen for the ceremony were naked except for small loincloths, and their bodies were daubed with red and black markings. The other hunters each carried a newly made spear.
The ceremony opened with the playing of drums and the beating of spears. This was designed to produce a heightened sense of expectation. When the drumming stopped, the mog-urs, clad in bear-skins, appeared and stood before the bear's cage. At that point, a mog-ur played the bullroarer to ward off all other spirits. The bear was allowed to drink water from a human skull while another mog-ur played a simple flute. The bullroarer was the roar of the cave bear in its physical form, and the flute was the sound of the spiritual voice of Ursus.
The hunters surrounded the cage of the cave bear, and when the music stopped, the cave bear was addressed as Ursus for the first time. The highest-ranking mog-ur asked Ursus to speak for the Clan in the world of the Spirits: to tell of the bravery of their men and the obedience of their women, to make a place for them in the afterlife, and to protect the Clan from evil spirits.
When the Mog-ur finished speaking, the hunters stabbed the bear with their spears while the three men chosen for special honors opened the cage. Then the hunters formed a protective phalanx around the bear. The chosen three climbed onto the bear and disabled its mouth by putting a log in it. (This was the most dangerous part of the ceremony and the source of the honor that came to those chosen.)
The Bear Ceremony concluded with a communion shared by everyone: the blood of Ursus. Afterwards, the Feast of Ursus was held in the Cave Bear's honor, during which his meat was served to the clans.