Rust Monster

Medium Monstrosity, Unaligned

AC 14     Initiative +1 (11)
HP 33 (6d8 + 6)
Speed 40 ft.

Ability Scores
STR 13 (+1) Save +1    DEX 12 (+1) Save +1    CON 13 (+1) Save +1
INT 2 (−4) Save −4    WIS 13 (+1) Save +1    CHA 6 (−2) Save −2

Senses Darkvision 60 ft.; Passive Perception 11
Languages —
CR 1/2 (XP 100; PB +2)

Traits

• Iron Scent. The rust monster can pinpoint the location of ferrous metal within 30 feet of itself.

Actions

• Multiattack. The rust monster makes one Bite attack and uses Antennae twice.
• Bite. Melee Attack Roll: +3, reach 5 ft.
  Hit: 5 (1d8 + 1) Piercing damage.
• Antennae. The rust monster targets one nonmagical metal object—armor or weapon—worn or carried by a creature within 5 feet. The creature must make a DC 11 Dexterity saving throw.
  On a failure: The object takes a −1 penalty to AC (armor) or to attack rolls (weapon). Armor is destroyed if reduced to AC 10; weapons are destroyed at −5 penalty. The penalty can be removed with the Mending spell.
• Destroy Metal. The rust monster touches a nonmagical metal object within 5 feet that isn’t being worn or carried. The object is destroyed in a 1-foot cube area.

Reactions

• Reflexive Antennae. Trigger: An attack roll hits the rust monster. Response: The rust monster uses Antennae.