Card Appearances:Dragonecro Nethersoul Dragon

In chapter 3, the Skeleton Knight used "Poltermerization" fusing the "Hellfire Sleeping Princess - Ghost Sleeper" on his side of the field and a "Hellfire Winged Lizard - Ghost Wyvern" from his Deck to Fusion Summon "Underworld Dragon Dragonecro". He used "Dragonecro" to attack Yusei's "Mighty Warrior" and steal its soul, forming "Mighty Warrior Dark Soul". At the end of the chapter, the knight ordered "Dragonecro" to attack "Lightning Warrior".