More recently, in late 2005 another different kind of marshmallow was added, the "Hidden Key". It is a solid yellow marshmallow that resembles the shape of an arched door (similar to the shape of a tombstone; flat at the bottom, flat sides with a round top). When liquid is added to the cereal, the sugar inside the marshmallow dissolves and the shape of a skeleton key "appears" as if "by magic". The new tagline for this is "Unlock the door with milk!"
In 2008, yellow and orange hourglass marshmallows were introduced (along with a new contemporary for Lucky named the Emerald Elder) with the marketing tagline of "The Hourglass Charm has the power to Stop Time * Speed Up Time * Reverse Time".