All or Nothing Coin

When making an ability check, saving throw, or attack roll, you can forgo rolling a d20 and instead flip a coin. Call heads or tails. On a success, you get a nat 20; on a fail, you get a nat 1. After using the coin roll a d20, on a 1, the coin turns to ash. Each time you use the coin, the DC of it withering increases by 1.