Rust monster

R Rust monster
Difficulty	8
Attacks	Rusts

R Rust monster
Difficulty	8
Attacks	Rusts
Base level	5
Base experience	68
Speed	18
Base AC	2
Base MR	0
Alignment	0 (neutral)
Frequency (by normal means)	Quite rare
Genocidable	Yes
Weight	1000
Nutritional value	250
Size	Medium
Resistances	None
Resistances conveyed	None

Rust monsters are an ungodly aggravation. They don't do any physical damage, but they will rust your weapon and equipment PDQ. The best way to deal with them is to either cancel them or to rustproof your equipment. Once you've done that, they're a piece of cake. Rust monsters are the only monsters who will eat when not tame.

Behavior in past versions

Before NetHack 3.1.0, rust (and other forms of object erosion) did not exist as such. Rust monsters and other things that caused rust instead reduced the enchantment; in the case of rust monsters this could go as low as -2. Thus rust monsters in older versions behaved more as modern disenchanters, save that their attack was still subject to an object's susceptibility to rust.