Quantumfly Buckler

Armor (shield), rare (requires attunement)

This colorful buckler has a stained glass butterfly emblazoned at its center. While holding it, you have a +1 bonus to AC. This bonus is in addition to the shield's normal bonus to AC.

This shield pulls potential outcomes from other parallel timelines. It has 6 charges and regains 1d4 + 2 expended charges daily at dawn. When a creature that you can see within 30 feet of you is hit with an attack, you can use your reaction to expend up to 4 of the shield's charges. When you do, that creature gains a bonus to its AC equal to twice the number of charges you expend, potentially causing the triggering attack to miss, as echoes from other timelines successfully block the attack. This bonus to AC lasts until the end of the turn. Immediately after using the reaction, roll a d4: if the result is equal to or less than the number of charges you spent as part of the reaction, you take 1d4 psychic damage for each spent charge. This damage ignores resistance and immunity.

I can't be everywhere at the same time, and I can't know every outcome. But I don't need to see every possibility—just the right ones.