A piano, where each block indicates a different note. By clicking on the blocks while using the harp, it is possible to play a song.
The 竖琴 is a 困难模式 制作材料, used only to craft the 魔法竖琴. While the Harp can be used itself, it has no functional use, and only makes sounds. It is sold by the 巫师.
When used, the Harp generates harp sounds. The sound's pitch is determined by the distance between the center of your character and the point clicked. Clicking the center of your character plays middle C, while clicking at a distance of at least that of the top or bottom of the screen plays C6 (two octaves above middle C). A difference of 1/48 of the screen height equals an interval of one semitone.
The 铃铛 and the 整蛊坐垫 have similar effects, although the whoopie cushion cannot change pitch