Digisoul (デジソウル, Dejisouru) is a phenomenon by which an aura of energy, manifested within a person can invoke Digimon evolution (Dub: Digimon Natural Ability, initialed to D.N.A).
In Digimon Savers, according to Bancho Leomon/Daimon Suguru, Digisoul is effectively human emotion given power, which can affect Digimon even subconsciously, as demonstrated on multiple wild Digimon early on. Those who can use and control this power can perform feats of incredible strength, as demonstrated by Masaru. Though it is fairly easy to control Digisoul for basic evolution to Adult, it seems one must overcome a major mental obstacle in order to achieve enough Digisoul to evolve their partner to the Perfect level. Additional power is needed to reach Ultimate, but that power must also be properly controlled by the user as well- failure to do so could result in destruction of Digivice. Burst Mode is even more difficult to master - if done improperly, such as with negative emotions, the partner goes into Ruin Mode, effectively destroys itself, reverting back to a Digitama.
Types of Digisoul
- Artifical Digisoul (人工デジソウル Jinzou Dejisouru): This is a synthetic form of Digisoul created by Kurata which was used to pseudo-evolve Gizmon: AT to Gizmon: XT through the use of Dark Digivices.
- Dark Digisoul: In Digimon Next, this was used by Kahara Shou and Inui Yuu. A Dark Digisoul uses the power of the Dark Area to empower a Digisoul, allowing evolution. However, it has serious effects on the user, Inui Yuu being knocked unconscious and requiring medical aid after his use of the Dark Digisoul. Strangely, Kahara Shou seemed to suffer no ill effects from his use of the Dark Digisoul, although this may be because he was in a far better state of health than Yuu and had darker emotions to begin with. It was used by Shou to evolve his Peckmon into Yatagaramon to fight Atlur Kabuterimon and Geo Greymon. It was used by Yuu in his fury at Trailmon's death to evolve Gaomon into a Black Gaogamon.