Lucky Coin

This accessory is dropped from Pirates in a Pirate Invasion.

Extra coins have a (20%) chance of dropping every time you hit an enemy with melee, ranged, magic or summon attacks. Damage return effects like with Turtle armor and Thorns Potion won't drop extra coins, nor will hitting background animals like bunnies. From the 20% chance, there is an even smaller chance that the dropped coins from any enemy are a few Gold Coins.

A good way to take advantage of this is with the Slime Staff. Against stronger enemies, the baby slime summoned by the staff will attack rapidly, but only do 1 damage per hit. This gives more chances for coins to drop.

Trivia

 * The coin may be a reference to Scrooge McDuck, as when he used his coin, he was always able to make massive profits.