In 2017 Clash of Clans has been hosting numerous in-game events where one can easily get lots of excess resources, XP and Gems.
On this page, I will provide you with about the current and future events and offer you help to get more out of these events. A number of them only provide XP and Gems, but you will get much more out of it with discounted troops along with the right strategy.
You could always see the current event, in game, in the news center in Clash of Clans:
Clash of Clans Wizard Event:
The Wizard Event is reducing the costs to cook a Wizards dramatically. In contrast to the other troop focus events, there are no extra Gems you can earn with this event, but it’s still useful to those of you using either Wizards during raid or in War.
So, if you are using appropriate attacking compositions with ground troops you will probably helpful from this event with the lower costs.