This opal gemstone, often affixed to an amulet, crown, or some other symbol of authority shines with a faint glimmer under moonlight but otherwise does not appear to be magical in any way. It is also guarded against divination magic and does not trigger magical detection abilities or spells. While attuned to the gem the wearer gains a number of benefits.
The wearer has advantage on initiative rolls and cannot be surprised, except when incapacitated by something other than nonmagical sleep. In addition, as long as the gem is within 5 feet of the creature attuned they are magically awakened and are able to act if they are sleeping naturally when combat begins. They also are able to take a reaction in the first round of combat before they have taken their first turn.
The gemstone also creates a small pocket dimension within itself that is capable of storing a suit of armor and a shield that the creature is capable of wearing. The wearer may use a reaction, in response to being attacked, to call the armor and/or shield out of the pocket dimension and magically don them. This can cause the attack to miss if it does not meet the creature's armor class while wearing the armor and/or shield. If either the armor or shield requires attunement placing them within the pocket dimension does not break this attunement. Once called it takes an action to doff the armor and shield, returning them to the pocket dimension.
Lastly, once per day, after failing a saving throw the wearer can choose to reroll the failed saving throw and they gain a +5 to the roll, if they do so they must take the second roll even if they have some other ability that would let them roll again and they cannot use this ability if they have already rerolled the save some other way. This ability resets daily at dawn.
Notes: Advantage: Initiative
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