History during the Lost Seasons
The Felgrand Armies are an army of people that was defeated by Grand during his invasion to the Island of Dragons and forced to join him in his quest to rule the souls and minds of everyone opposite him.
They are sent by Grand to defeat all unwelcome guests that arrive to the Island of Dragons. It is extremely dangerous to face them in duel because the loser is consumed by his Dark Desire transforming into a Dark Duelist to join the Felgrand Armies
They are all defeated by Yugi Muto and Joey Wheeler with Rakum Gensutku and Riot Gensutku both being part of this army until they are defeated as well and then forced into a Worm Hole Fissure after their betrayal.