Rust monster

Rust monster
Characteristics
Alignment	Neutral
Type	Aberration (3rd edition)
Stats	Open Game License stats

A rust monster is a fictional creature from the Dungeons & Dragons fantasy role-playing game that seeks out and consumes metal, often the armor and weaponry of players' characters. Originally inspired by a cheap plastic toy, the rust monster was one of the first monsters specifically created for D&D, and has been included in every edition of D&D, although various aspects of the creature have changed from edition to edition. Although in most editions, the rust monster has been a non-lethal creature with little or no way of physically harming players' characters, it is the rust monster's ability to destroy a character's cherished and expensive weapons and armor in mere seconds that makes it a particularly fearsome opponent.

In the early 1970s, Gary Gygax was playing Chainmail, a wargame that bore some precursors of Dungeons & Dragons. In order to give his players as many different challenges as possible, Gygax was always on the look-out for new monsters. Although he was able to draw on pulp fiction and sword and sorcery stories for many of them, he also looked through dime stores for figurines that could be used in battle. On one of those occasions, he came across a bag of small plastic toys euphemistically labeled "dinosaurs". Several of these were odd enough to catch his eye, and he used them to represent several new monsters, including the bulette and the owl bear. One of the figurines looked like an absurd lobster with a propeller at the end of its tail, and Gygax could think of no fearsome powers for such a monster. After some thought, he came up with the amusing idea that this non-lethal creature would not attack characters in order to eat them, but rather to eat their hard-earned possessions.

When Gygax co-developed the game of Dungeons & Dragons, the rust monster rapidly migrated to the new game system, and made its first published appearance in the first supplement to the original rules, Dungeons and Dragons Supplement I: Greyhawk. The rust monster was described as "inoffensive" but "the bane of metal with ferrous content". The creature was attracted to the smell of iron-based metals, and any such object touched by the creature instantly turned to rust, which the rust monster would then consume. The rust monster could also use this power in its defense, since any metal weapon used against it would also turn to rust. Characters hoping to save their armor and weapons by avoiding it found they could not outrun it, since it moved about four times as fast as the average character.

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Wikipedia