Gennai

Gennai is a mysterious being which the DigiDestined encounter after the battle with Devimon. Gennai comes to the first DigiDestined as an old man but in the second series, he comes to the new DigiDestined as a very young person guarding the the Digi-Eggs from Piedmon and the other Dark Masters; Gennai claims to have been there at the start of the Digital World.

His young-self was voiced by Hiroaki Hirata(Japan) & Jeff Nimoy (English) while his old self voiced by Joji Yanami (Japan) & Michael Reynolds (English).