Rouxls Kaard is an NPC and temporary minor antagonist featured in Deltarune. He introduces himself as the Duke of Puzzles, and attempts to thwart the protagonists by forcing them to solve his puzzles. Additionally, he attempts to hinder them with a mini-boss fight, by placing a "control crown" on a C. Round. After being defeated, he refers to his prior actions as "Tests of [their] Heroick Resolve."