Booster or to light candles in a cake to win some boosters. What must I do to get those?
No more candles to be lit at the moment, I think.
I believe that most of these challenges in their games are on mobile; therefor make sure your apps are up to date and that you play connected either to your Facebook or your Kingdom account.
Even then, it still can be a random thing. Some friends of mine had challenges I never got.
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