Special Items
There are two kinds of items in battle, one appears in the match-3 area, one shows at the bottom of your screen, their effects show below:
In the match-3 area:
All the special items need to be eliminated by making matches next to them twice.
At the bottom of your screen:
You can only use these special items when you eliminated some chests in the match-3 area, all these four items share the same count of use.