You rented it because the cover looked like a costume party. A kid, a weird bird-alien thing, some cartoonish monsters standing around like they’d just walked in from a Halloween store. Then you popped in the cartridge and the title screen dripped blood down the letters. That bait-and-switch is basically the whole story of Monster Party.
Bandai published Monster Party for the NES in North America in June 1989, built by the Japanese studio Human Entertainment. The setup: a kid named Mark gets recruited by an alien griffin named Bert to clean up a place called Dark World. Bert fuses with Mark, so collecting the right pill mid-level turns you into Bert for a stretch — flight, a stronger attack, the works — before you shrink back down to swinging a baseball bat at things that used to be human. It’s a platformer underneath all the weirdness, eight levels, password saves, mostly straightforward. The weirdness is the point.
Here’s the part collectors actually bring up: the American version everyone played is the censored one, and the original was stranger. Monster Party was meant to come out in Japan first as Parody World: Monster Party, and it never did — Bandai’s Japanese arm canceled it. That build sat lost until a copy surfaced on a Yahoo auction years later and got dumped and documented on The Cutting Room Floor. What it revealed: a title screen soaked in even more blood, a boss riffing on the ape army from Planet of the Apes, a Gremlins mogwai turned into Bandai’s version of a plain house cat for the US, a musical plant lifted straight from Little Shop of Horrors, a Medusa fight cut entirely, and a grim reaper that leaned hard on Alien’s xenomorph. Nintendo of America’s lawyers clearly had notes.
What Nintendo’s censors somehow missed is the funnier detail. This is the same company that scrubbed crosses out of Castlevania and wouldn’t let a game so much as gesture at religious imagery, and yet Monster Party shipped with actual blood effects and a character casually dropping the word “hell.” Nobody’s ever nailed down why that slipped through while a Medusa boss didn’t. It’s just one of those inconsistencies retro collectors like to argue about over a beer.
None of that made Monster Party a hit. It stayed a niche title — a small, loyal following of players who remember it as the NES game that looked like a party and played like a fever dream. That obscurity is exactly why it’s worth a look now instead of the fortieth time through a game everyone already owns. If you’re building out a collection beyond the obvious Black Box titles and licensed platformers, this is the kind of cartridge that rewards knowing the story behind it — a lot like Little Nemo: The Dream Master, another late-80s NES release that’s more interesting than its shelf presence ever suggested.
Monster Party isn’t rare in the way a Nintendo World Championships cart is rare, but it isn’t cheap either. A loose cartridge runs in the neighborhood of $15 to $20 today, a complete-in-box copy climbs past $100, and sealed examples have sold north of $400 when one actually surfaces — proof of how few people held onto the box and manual for a game they figured they’d trade back in. That’s the pattern with a lot of cult NES titles: the cartridge alone is common enough, but a genuinely complete copy with unworn box corners and an intact manual gets scarce fast. If you’re thinking about having a copy authenticated, our grading process walks through exactly what we’re checking for on a cartridge like this one.
It’s not a game anyone’s going to call a masterpiece. It’s just proof that in 1989, Nintendo’s seal of approval could still let something genuinely off-kilter through the door.