Adamantine Assassin (5e Creature)
From D&D Wiki
Medium construct, unaligned
Saving Throws Dex +12
Immutable Form. The adamantine assassin is immune to any spell or effect that would alter its form.
Magic Resistance. The adamantine assassin has advantage on saving throws against spells and other magical effects.
Magic Weapons. The adamantine assassin's weapon attacks are magical.
Gouge. Whenever the adamantine assassin hits with any finesse melee weapon that deals piercing or slashing damage the target takes an additional 13 (3d8) slashing damage (included in the attack).
Multiattack. The adamantine assassin makes three melee attacks.
Rapier. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 11 (1d8 + 7) piercing damage plus 13 (3d8) slashing damage.
An adamantine assassin is the perfect tool for military scouting, political assassinations, bodygaurding, and general combat. Its relatively small and durable frame make it both a nightmare to chase down and kill while its extreme precision make it extremely effective at combat. The only drawback to the adamantine assassin is how costly it is, both in terms of the materials and magic required to produce one.
Constructed Nature. An adamantine assassin doesn't require air, food, drink, or sleep.