The following is a list of recurring voice actors and the characters they play (of course, for more complete/accurate lists, simply view the credits for each episode). If there are any errors, let me know.
Wizardmon5
Donutzilla, Wizardmon5, Tom, Announcer, Becca, Server (Episode 2)
Phorpus
Phorpus, High-Voice Backwards Boy, Darth vader
Leus
Leus
Amedeus
Amedeus, Jason, Jeskid
Alsace
Alsace, Geoff, National Geographic Narrator
Zatch
Zatch, Gus
Bey
Bey, Gavino, Little Girl, Becca
Billyz90
Jason, Opaque
TKdademon
Maserder, TKdademon