Holy Ring

The Holy Ring (ホーリーリング) is a golden ring, of varying size and shape, that is worn by several Digimon and marks them as Holy-species Digimon. These rings give the Digimon great power relative to their holiness and where they are worn, but if the Digimon loses its holiness, either by falling from grace like Cherubimon (Evil) or by being possessed like Tapirmon in Digimon Frontier, it also loses its Holy Rings. Holy Rings are usually inscribed with DigiCode which reads Dejitaru Monsutā (デジタルモンスター).

Digimon Adventure
Gatomon's Holy Ring, which she also calls her "tail ring", gives her the power of a Champion; without it she is as weak as a Rookie. During the Digimon Emperor's initial invasion against the Digital World, Gatomon flees from a Unimon brainwashed by the Emperor's Dark Rings, but she loses her tail ring when the Unimon catches it with his hoof. The loss of the tail ring lowers Gatomon's power to the point that she can Armor Digivolve like the other DigiDestined partners, and when Gennai later finds it, he uses its holy power to hold back the darkness encroaching upon the Digital World, and to allow the DigiDestined to DNA digivolve.

Shortly after Arukenimon creates BlackWarGreymon, the DigiDestined decide to search for Gatomon's tail ring, in order to re-empower her. Kari, Yolei, and Ken fall through a hole to the Dark Ocean while searching, but Gatomon and Aquilamon are able to DNA digivolve to Silphymon to save them from a Blossomon created by Arukenimon.

Just after the battle with MaloMyotismon ends, Gennai returns the tail ring to Gatomon and explains what he had used it for.

Digimon Frontier
When a Tapirmon attacks the DigiDestined, Neemon notices that it is not wearing its Holy Ring, and Bokomon explains that Digimon that have fallen under the control of evil beings like Cherubimon cannot wear Holy Rings.

Digimon World Data Squad
Salamon, who lives in Sneyato Forest, gives Marcus a Holy Ring after he speaks to the Digimon. This Holy Ring allows Yoshi to digivolve Lalamon to Salamon whenever she desires.

List of Digimon with Holy rings

 * Angewomon (one on left ankle)
 * Chaosmon (one on right forearm)
 * Cherubimon (Good) (two; one on each ear)
 * Gatomon (one on tail)
 * Gatomon X (one around chest)
 * Goldramon (two; one on each forearm)
 * Hououmon (two; one on each ankle)
 * Kudamon (2006 anime) (one around neck)
 * Liollmon (one around neck)
 * Lucemon (four; one on each wrist and ankle)
 * MagnaAngemon (one on right wrist)
 * MarineAngemon (one around neck)
 * Parrotmon (two; one on each wrist)
 * Rapidmon (Armor) (two; one on each thigh)
 * Salamon (one around neck)
 * Salamon X (one around neck)
 * Tapirmon (one on left foreleg)
 * UltimateKhaosmon (one on left wrist)