Wondrous item, rare · 2024 version below
If the stone is touching the ground, you can use an action to speak its command word and summon an earth elemental, as if you had cast the conjure elemental spell. The stone can't be used this way again until the next dawn. The stone weighs 5 pounds.
The 2024 Dungeon Master’s Guide revised the magic items, and the SRD 5.2 carries the new text. What changed:
Same rarity and attunement; the text is reworded for the 2024 rules glossary.
While touching this 5-pound stone to the ground, you can take a Magic action to summon an Earth Elemental. The elemental appears in an unoccupied space you choose within 30 feet of yourself, obeys your commands, and takes its turn immediately after you on your Initiative count. The elemental disappears after 1 hour, when it dies, or when you dismiss it as a Bonus Action. The stone can't be used this way again until the next dawn.
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