I've noticed random items while sweeping. It sometimes drops jar of gems and building hammers is it a part of the balloon event?
The Balloon event had not begun the last time I was ingame, but the way the Balloon event works is that while playing certain features such as HBM, Dungeons, Arena, etc....you can receive one of the two items selected for that particular event, which can be exchanged for the items being offered. I personally have never seen either the hammers or jars of gems being the selected items, however I guess it is possible.
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