Fable's End (Patreon)

Weapon (mace), very rare (requires attunement)

You gain a +1 bonus to attack and damage rolls made with this magic weapon. Whenever you roll a 20 on an attack roll with fable’s end against a Large or smaller creature, it must succeed on a DC 15 Charisma saving throw or be banished to its native or other plane of existence. At the end of its next turn, the target reappears in the space it left or in the nearest unoccupied space if that space is occupied. You banish and score a critical hit against fey creatures on a roll of 19 or 20 with this weapon. Fey creatures have disadvantage on the saving throw. When a creature is banished in this way, the weapon’s center emits a brilliant magenta flash of light. 

When the fey folk came to town,
The children went away,
The shepherd offered wool and meats,
The milkmaid offered whey

The baker offered cake and pie,
And tempted them with sweets,
The tailor offered silken dress,
With ribbons, bows and pleats

But when the the smithy came to town one day,
And saw that empty bed,
The only thing he'd give the fey,
was the taste of iron instead.