Source: Dungeon Master's Guide

Wondrous Item, Very Rare (Requires Attunement)

While wearing this amulet, you can take a Magic action to name a location that you are familiar with on another plane of existence. Then make a DC 15 Intelligence (Arcana) check. On a successful check, you cast Plane Shift. On a failed check, you and each creature and object within 15 feet of you travel to a random destination determined by rolling 1d100 and consulting the following table.

1d100 Destination
01–60 Random location on the plane you named
61–70 Random location on an Inner Plane determined by rolling 1d6: on a 1, the Plane of Air; on a 2, the Plane of Earth; on a 3, the Plane of Fire; on a 4, the Plane of Water; on a 5, the Feywild; on a 6, the Shadowfell
71–80 Random location on an Outer Plane determined by rolling 1d8: on a 1, Arborea; on a 2, Arcadia; on a 3, the Beastlands; on a 4, Bytopia; on a 5, Elysium; on a 6, Mechanus; on a 7, Mount Celestia; on an 8, Ysgard
81–90 Random location on an Outer Plane determined by rolling 1d8: on a 1, the Abyss; on a 2, Acheron; on a 3, Carceri; on a 4, Gehenna; on a 5, Hades; on a 6, Limbo; on a 7, the Nine Hells; on an 8, Pandemonium
91–00 Random location on the Astral Plane