Ever wished there was an opening you could play almost every game, with little concern for what your opponent does across the first few moves? Maybe the colle system is just what you're looking for. Described as a system, rather than an opening, the colle is a series of moves: d4-e3-c3-Nf3-Bd3-Nbd2 which you can play against almost anything. Many players specialise in this opening and become exceptionally strong at it, preferring to be great at one variation instead of becoming just ok at many different opening variations.
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