Ghosts 'n Goblins
The "Ghosts 'n Goblins" franchise stands as Capcom's 13th best selling game franchise, having sold over 4.2 million units. It is generally well regarded by critics and somewhat notorious for its traditional high level of difficulty. Additionally, the franchise frequently makes cameo appearances (the character of Arthur in particular) in other Capcom titles, the latest of which being "Ultimate Marvel vs. Capcom 3".