Sword Keeper (5e Creature)
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Medium humanoid, lawful neutral
Loyalty. The Sword Keeper can't be Persuaded or Intimidated
Hacking Slashing. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 8 (1d8 + 4) slashing damage, plus 13 (3d8) acid, cold, poison, fire or lightning damage.
Sword keepers are humans mutated by magic, so they don't die by age, are totaly loyal to who designed them for guard a sword, and any sword they use be a magical sword.