Monster Party (パーロディワールドモンスターパーティー, Parodi Warudo Monsutā Pātī, Parody World: Monster Party?) is a video game for the NES, released in the U.S. in 1989 by Bandai. It was and remains a relatively obscure platform game for the console, having a small following among some players. The game both plays homage to and parodies horror pop culture, alternately featuring enemies and locations based on classic horror icons, and parodic reinterpretations.
In the 2000s the game became infamous in online gaming circles when a prototype screenshots of a Japanese Famicom began circulating, showing that the game was originally intended to be much darker and more morbid than the relatively light-hearted version that was ultimately released to American gamers. No version of the game was ever released in Japan. On May 26, 2011, a prototype of the canceled Japanese release was listed on Yahoo! Japan auctions, closing at a very high price of ¥483000 (approximately $6000 in American dollars).