In Ukraine, what unique decoration is often included on Christmas trees for good luck?

Spider web ornaments

Who unleashed evil and misery onto humanity by opening a forbidden box? Which male tennis player holds the record for the most men's singles Wimbledon titles? What team did Kevin Durant leave the Oklahoma City Thunder for in 2016? What was the group of American writers disillusioned after World War I known as? What is the plural form of 'vertex'?