Slight
A Little
A leader in boots has a slight edge over one without boots. It's not much, but even a little advantage is better than nothing.
きん
わず
None
Getting that slight edge over other leaders allows your leader to become the king (きん).
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Finish up what ever you are doing on the other tab(s), then close them to continue.
The update will complete automatically once the other tab(s) are closed.