The Curious Map is a special item that appears in the extra room of the Hall of Champions in the Sony, Xbox One and Pc Versions of Shovel Knight. It's a slightly different item in each version and both trigger an exclusive sidequest. A hint about the existence of this map can be heard from an NPC found exclusively in the Shortcut? area in both versions.
Sony Version Edit
"A map with a strange symbol... perhaps it was lost by someone?" - Sony Version description
The Sony Curious map has an omega symbol on it. Acquiring it leads Kratos to appear on the map screen as a roaming encounter.
Xbox One/Pc Version Edit
"A map with a weird symbol... and there are some extra markings here! - Xbox One/Pc description