Book of the Elements (5e Equipment)
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Wondrous item, Very Rare (Requires attunement from someone with at least one elemental spell.)
The book is a host of colors, from red to brown to blue and finally white. It has 4 locks on the side, each with the symbol of one element.
Elemental Prison. This book is meant to be a prison for elementals. When you speak the command word, it sucks in an Elemental of your choice to be released later. If you fail a DC 10 Strength Saving Throw, though, you get sucked in too. A second command word with the element type releases an elemental of your choice. depending on how they were imprisoned, they will either be begrudgingly loyal to you, or somewhat loyal where they will fight, but if they get wounded they will abandon you at a moments notice. The book can only hold 8 elementals.
Elemental Spells. Even if there is no elementals in the book to release, you can still do elemental magic. You gain the ability to prepare the following spells (all homebrew): Elemental Blow, Elemental Edge, Elemental Strike, Elemental Bolt, Elemental Wrath, Elemental Storm.