To get the hard badge, pay attention to level 13, 15, and 19.
You can achieve 100% in Level 13 by watching the walkthrough.
In Level 15, remove either the whole blue/red bar, and you can get more than 50% (mine is 58%).
In Level 19, draw an oblique line across two columns, you should get over 80% easily (mine is 83%).
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 "Candy Jewels Story")
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 "Path of Honor: Chapter 1")