Umbrella

The Umbrella is a held item that can either be found in surface chests, but not dropped by Umbrella Slimes suprisingly (Umbrella Hats are dropped by Umbrella Slimes). When used, the umbrella appears above your character and allows the player to fall at a slower rate. It prevents falling damage, and replicates the effect of the Featherfall Potion.

Trivia

 * Is likely a reference to the Nintendo game "Kirby". In said game you can obtain an umbrella of the same design, with the same usage.