If Zhang Gui concealed his real battle strength in the public, besides avoiding from outsiders' disputes and the embarrassing conflicts in Huaiyuan Palace, the biggest benefit was that Zhang Gui could easily deal with more difficult situations at the critical moment.
At any time, concealing one's battle strength would bring unimaginable benefits. A black iron knight was too weaker than an earth knight in battle strength. As long as the opponent underestimated Zhang family's overall strength at the critical moment, Zhang family would be safer and reverse the situation.
After killing Han Zhengfang, Zhang Tie found that he became increasingly "grimmer" and more "cunning" in considering and dealing with problems.
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The thunder hawk moved very fast and smoothly on the way.