Fortune's Fivepence

This electrum coin has a smiling human woman’s face on one side (heads) and a scowling fiendish woman’s face on the other (tails). While you’re within 30 feet of the coin, you can summon it to either your hand or pocket by speaking its command word as a bonus action. Despite its unique appearance, this coin can be spent like a normal coin.

Fate Flip. This coin has 2 charges. You can attempt to regain expended charges once every 24 hours by flipping a coin. The coin regains all expended charges if it’s heads, or 0 if it’s tails. When the coin is on your person and your total for an attack roll, ability check, or saving throw is 10 or lower, you can expend 1 of the coin’s charges to channel its magic and forge your own luck. When you do, flip a coin. If it’s heads, roll a d10 and add it to the total of your roll. If it’s tails, you subtract 1d10 from the total instead. The coin loses this property if using it in this way reduces the total of your roll to 0 or lower.