Blunderbase

Colle System

The Colle System starts 1. Nf3 c5 2. e3 g6 3. d4 Bg7 4. dxc5 Qa5+. The opening book names 3 variations of it, under ECO A04 to A40.

The main line, move by move

Starting position8 more to go

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All 3 Colle System variations

  • A04Rhamphorhynchus Variation1. Nf3 c5 2. e3 g6 3. d4 Bg7 4. dxc5 Qa5+
  • A40Pterodactyl Variation1. d4 g6 2. Nf3 Bg7 3. e3 c5 4. Bd3 Qa5+
  • A40Siroccopteryx Variation1. d4 g6 2. Nf3 Bg7 3. e3 c5 4. Bd3 cxd4 5. Nxd4 Qa5+

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