Arsenal Ring (5e Equipment)
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Ring, very rare (requires attunement)
A ring that holds an armory inside it, allowing the wielder to be prepared for any situation.
This magic ring has 10 charges with which to activate its ability. While attuned to this magic item, as a bonus on your turn, you may transform this item into a weapon with a +3 bonus to its attack and damage rolls. You may turn the ring into a simple melee weapon (1 charge), a simple ranged weapon with 20 pieces of appropriate ammunition in an appropriate case if applicable (2 charges), a martial melee weapon (3 charges), or a martial ranged weapon with 20 pieces of appropriate ammunition in an appropriate case if applicable (4 charges). As a bonus action while you're holding this magic item as a weapon, you can transform it back into a ring at no cost. This ring regains 1d6 + 4 expended charges daily at dawn.
If this item leaves your possession while in weapon form, it transforms back into its ring form after one (1) minute has passed. Any ammunition created by this ring is ordinary ammunition except it disappears within six (6) seconds of being used. You are not automatically considered proficient with weapons this ring takes the form of.