Our St Patrick's Day Event has just started. When you complete an Leprechaun quest between now and March 30th, you will win one of these new prizes. When you receive a prize from him, he will tell you how many minutes you should wait before you will win another bonus prize from completing a quest.
Just making a note for others that the prize shows up at the top of the page. I was not aware of that and did about 18 quests in a row before realizing the prizes don't appear next to the currency like halloween snowman prizes.
