Small aberration, lawful neutral

Armor Class 13
Hit Points 77 (14d8 + 14)
Speed 5 ft., 30 ft. (hover)

12 (+2) 17 (+3) 12 (+1) 12 (+1) 10 (+0) 12 (+1)

Skills Stealth +7
Damage Resistances acid; bludgeoning, piercing, and slashing from nonmagical nonmetal weapons or magical metal weapons
Damage Immunities fire, lightning, poison; bludgeoning, percing, and slashing from nonmagical metal weapons
Damage Vulnerabilities cold
Condition Immunities deafened, poisoned
Senses darkvision 90 ft., passive Perception 10
Languages Common
Challenge 1 (200 XP)


  • Exceptionally Quiet. The rexav ads twice its proficiency bonus to Stealth, and it has advantage on Stealth checks.
  • False Appearance. While the rexav remains motionless, it is indistinguishable from a normal sword.
  • Magic Resistance. The rexav has advantage on saving throws against spells and other magical effects.
  • Rust Metal. Any nonmagical weapon made of metal that hits the rexav corrodes. After dealing damage, the weapon takes a permanent and cumulative -1 penalty to damage rolls. If its penalty drops to -5, the weapon is destroyed. Non magical ammunition made of metal that hits the rexav is destroyed after dealing damage.


  • Multiattack. The rexav makes two attacks with it slash.
  • Slash. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 6 (1d8+2) type damage.


A rexav’s silvery body is smooth and metallic, tapering like a long dagger or narrow sword. Its substance is hard and holds a sharp edge like a real weapon, with a small, rounded leg with six faceted gem-like eyes around it that resemble a jeweled pommel and a wire-wrapped hilt. The rexav can unwind the wire around the hilt to form a cluster of tiny worm-like legs, but despite their seeming thinness are strong enough to allow it to perform a vigorous dance in battle, swinging their bladed body in wild slashes.

If they perceive danger, however, they can retract these legs and remain motionless like a discarded weapon.

Metalbane. A rexav eats ferrous metals, including adamantine as well as iron and steel, in a manner similar to a rust monster. They are intelligent creatures and can converse tersely in ringing metallic tones, and may bargain with passersby for metal to eat, though they may not be easily bought off with simple iron spikes when a feast of armor presents itself.

Those seeking to defend themselves against a rexav’s attacks may find that their own metal weapons pass harmlessly through the rexav’s form. Non-metal weapons and magical metal may wound them, though their steely bodies are difficult to harm. While their bodies appear metallic, they never rust or corrode and are not subject to the attacks of rust monsters.

In fact, rexavs do breathe in a strange way, absorbing air through their metallic substance to maintain their curious form of life. In death, however, the vitality that maintains their impervious material fades and the metallic elements within their bodies begin to corrode.

Section 15: Copyright Notice

Ultimate Treasury (5E) © 2023, Legendary Games; Authors: Jason Nelson, Loren Sieg, Pedro Coelho, Matt Goodall, Linda Zayas-Palmer, Thurston Hillman, Jeff Ibach, and Alex Augunas

This is not the complete section 15 entry - see the full license for this page