Tome of Runes (5e Equipment)
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Wondrous Item, legendary (requires attunement)
This tome is filled with the knowledge to create runes. If you study this tome for 10 hours, you acquire the knowledge to create runes. To create a rune, you must expend an action, spell slot (any level), plus select a spell and type of rune. In addition to spending an action and spell slot, you also gain a penalty to your spell casting ability equal to half of the chosen spells level (minimum of 1, rounded down) until that rune is activated. To select a spell, choose a spell that you can cast. If the spell requires materials, provide them. To select a type, choose from one of the following runes:
Weapon Rune: You create the rune on a weapon. You may activate the rune by speaking a command word (your choice). When the rune is activated, the chosen spell lingers in the weapon. Hitting a target with that weapon will cause the spell's effects on the target. After 1 minute has passed, the effect disperses and the rune loses a charge. The rune begins with charges equal to 20-the spells level (0 for cantrips). When the last charge is expended, the rune disappears.
Armor Rune: You create the rune on armor, clothes, or a cloak. You may activate the rune by willing it to activate (no action required). When you do, you gain the effect of the chosen spell. If the spell requires concentration, it doesn't require concentration, and will last for its full duration. The effects of the spell can stack up to 3 times as long as you activate the rune multiple times. When the rune is activated, it loses a charge. The rune has charges equal to 5 + your AC - the spells level (0 for cantrips). When the last charge is expended, the rune disappears.