Nilrem Coranerius is the main antagonist of Benny, Leo and Johnny vs. Coranerius. He is a wizard from the fictional fictional book of the same last name. His goal is to take the throne of King Arturo so he can make everybody do his bidding without one little mistake, and condemn anyone who makes even one mistake (no matter what size) to eternal sleep inside dark crystals or death. He has a magic mirror and forms hideous-looking minions with his sceptre-wand.
Coranerius' first name comes from the name "Merlin" spelled backwards, while his titular last name comes from the Spanish word "corazón" and the Portuguese word "coração", both meaning "heart", the word "nero" meaning "black" in Italian, and the Latin masculine singular suffix "-ius", thus his alias being "The Black-Hearted Anti-Merlin".
In the crossover, Maverick and King Sethrope work for him.