DigiCore

The DigiCore, said to be at the center of a Digimon's body, is a type of nucleus, and a powerful energy source, that houses a Digimon's primary data, and is analogous to its soul; a Digimon can continue to exist long after its body has rotted away so long as its DigiCore remains unharmed, but this also means that the DigiCore is a point of failure for the Digimon, as the Digimon will immediately cease functioning if they lose their DigiCore. As most Digimon only have one DigiCore, they usually hide it deep within their body, although many     have rotted to such an extent that their DigiCores are visible, and the most powerful of Mega Digimon, such as the Digimon Sovereigns, each have a dozen DigiCores that orbit their bodies. In addition, when two Digimon undergo DNA Digivolution, their DigiCores are normally totally fused, resulting in a single new Digimon; when this process is left incomplete, the resulting Digimon maintains its form in a very unstable state. UltimateChaosmon, who is both an extremely powerful Mega Digimon and an incomplete DNA Digivolution, is thus unable to store its DigiCores within its body, so they manifest bare.

Digimon Adventure 02
One of the cores was given to Gennai by Azulongmon to aid the DigiDestined in the battle in Real World against and, granting the Digimon the power to digivolve to their Ultimate level once again, while also allowing  to become  for the first time.

After Imperialdramon's core was damaged by SkullSatamon during the Digivolution process, the remaining Digimon sacrificed their power to restore and re-empower Imperialdramon, allowing him to Digivolve into Imperialdramon Fighter Mode, easily turn the table against SkullSatamon and defeat him.

Later, Azulongmon gave another one to in order for him to Digivolve to  and combat against  who had gone to the Real World following the barrier between worlds being weakened after the lost of Digicore and the destruction of six Destiny Stone.

Digimon Fusion
is able to separate the DigiCores of Digimon from their bodies using the Dark Stone, a fate he inflicts on the Dark Generals,, , and. In the case of the Dark Generals, it allows him control over the resulting mindless body. These DigiCores are imprisoned in, a place where spirits can materialize.

Digimon Next
The Black DigiCore is an artifact that appears in Digimon Next. uses them to enslave Digimon and humans to his will by inserting them into the target.

Digimon ReArise
In the past, when a large amount of Digital Points opened up in the Digital World, bringing a large amount of Spiral, the and  used the power of the Four Holy Beasts' DigiCores to open a distortion to attract all the Spiral into the same place so that they could deal with them all at the same time. Once all the Spiral arrived in the same place, they used the distortion to send them all to the Dark Area which was enough to get rid of all the Sprial for a long period of time.

A long time later, before the Four Holy Beasts slumber to restore the balance of the Digital World, they give some of their DigiCores to their Deva subordinates so that they could use their power to help defeat the Spiral, as they had since returned. gives one to which causes it to digivolve to  for the first time. Later, gives one to  which allows it to digivolve to  for the first time. Takumi Hiiragi, having learned that the Four Holy Beasts gave the Deva their DigiCores, has attack and nearly kill  and takes its DigiCore by force.

Later, when a Digital Point opens up in the Digital World, tries to use one of the DigiCores to re-enact their plan from the past, though the other Deva disagree due to the Four Holy Beasts no longer being around to mitigate the damage the distortion would do to the Digital World and Human World as that was the only reason they were able to successfully act out the plan in the first place. Undeterred, Caturamon enlists the help of of the  and gives it another DigiCore so that it would get more power to try and mitigate the effects of the distortion. Unable to do so however, the effects of trying to control the distortion instead causes Ophanimon's emotions to go out of control, leading it to Mode Change to and try to deal with the problem by destroying the Human World, as that is where the Digital Points supposedly originated from. Realising the error of its ways, Caturamon teams up with the Humans and they are able to distract Fallen Mode long enough for Caturamon to retrieve the DigiCore, returning Ophanimon back its senses. The two then apologise for their actions, realising the other Deva were right after all and that trying to use that same plan again was too dangerous.