[@Psyker Landshark] Actually a very good question. I like to think that Dark Digivolution occurs when a Tamer is influenced by dark emotions, resulting in a Digimon losing control. I suppose a good example would be [url=https://wikimon.net/images/9/91/Greymon_black2.jpg]BlackGreymon[/url] that would normally Digivolve to [url=https://wikimon.net/images/1/1f/Metalgreymon_virus.jpg]MetalGreymon (Virus)[/url] might Digivolve to [url=https://wikimon.net/images/1/1f/Skullgreymon.jpg]SkullGreymon[/url] while under the influence of a Tamer's negative emotions.