Slime Monster Game from Mattel (1977)

Company: Mattel | Release date: 1977 | Ages: 5+ | # of players: 2-4 | Where to purchase: eBay

“Don’t let the Slime monster ooze on your player!”

In Mattel’s Slime Monster, players competed to defeat a creature that invaded a town and oozed the green, viscous compound.

Mattel introduced Slime in 1976, packaging the non-toxic, water-soluble combination of guar gum and borax in trashcan-shaped packaging. The Slime Monster game represented the company’s first attempt to “gamify” the toy.


The game board consisted of a colourfully illustrated town with a network of streets and buildings. The town was surrounded on each side by a natural (ocean, river, forest) or manmade landmark (highway).

Each player selected a pawn and started their monster-fighting quest at the town’s High School while the Slime Monster began its reign of terror near the center of the board. In addition to towering over the pawns, the monster also contained a reservoir of Slime, courtesy of the 4oz container of the compound that Mattel provided with each game.

Gameplay was facilitated via a uniquely designed spinner. Each spin served double duty, directing both the movement of the monster and the player. Each turn, players attempted to guide the Slime Monster near an opposing player and “slime” them. If the Slime covered a player and caused the pawn to fall over, they had to re-start from the beginning.

While trying to avoid a slimy fate, players attempted to make their way to the town’s armory to secure a landmine. Once the weapon had been acquired, players could attempt to engage the monster. If a spin caused them to land on one of the six spots near the monster’s feet, they placed their landmine beneath his feet and were granted a second spin. Spinning a “Blast” designation allowed them to activate it, knocking the Slime Monster over and winning the game.


A complete game included 1 game board, 1 Slime Monster, 4 multi-coloured people pawns, 4 Land Mines, a spinner, and a container of Slime. Printed instructions were included in the box.

The mess made while playing the game was an enormous appeal for kids. Extended gameplay typically resulted in pockets of Slime across the board, with the largest deposit occurring when the creature was tipped over. For this reason, it can be challenging for collectors to find a “clean” game with the Slime still intact.

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