Why won’t Toughest: Venom Kracko unlock? (Super Kirby Clash)

(Story) I finished all the quests up to Toughest: Blocky in Seaside, and all the quests up to Toughest: Spark Bonkers in Dunes, shouldn’t the tenth ordeal (Toughest: Venom Kracko) unlock now? What am I missing?