Laszlo Polgar: Chess Middlegames Pgn Better Extra Quality
You can upload Polgar’s middlegame positions into training software like Chessable or LucasChess. This allows you to drill the positions until the patterns are hard-coded into your subconscious.
Laszlo Polgar's middlegame specific work, often titled (distinct from the 5334 book), features 4,158 positions categorized into 77 tactical and positional themes. laszlo polgar chess middlegames pgn better