Chess Tips and Chess Middlegame theories

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Most Important Middle Game Chess Principles to Follow

Chess Middlegame for Beginners: The Complete Tactics and Strategy Guide for Beginners: Klein, Cory: 9781986248556: : Books

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The Importance of Middle Game Tabiyas - Internet Chess Club

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Lesson 6 – What you should do in the middle-game –

Middlegame Strategy Request] What can be done as black playing the Sicilian defense against a long castle? I find myself losing in this position to players rated much lower than me