Diviner's Dice (Patreon)

Wondrous item, rare (requires attunement)

This set of three six-sided crystal dice is weakly connected to the tides of fate. You can roll these dice as an action and record the numbers rolled. Once rolled, you can't record any other numbers in this way until the next dawn. While you have the dice on your person, you can use a reaction when you or a creature you can see within 60 feet of you makes an attack roll or ability check to add or subtract one of the recorded numbers from the attack roll or ability check's total. You can wait to use this reaction until after the creature rolls the d20, but must decide before the GM says whether the roll succeeds or fails. Each recorded number can only be used once. You lose any unused recorded numbers daily at dawn.

Our fate is the product of thousands of chances that come together, turning our destinies into a mere gamble. And, like any game of chance, someone will always find a way to cheat.