Formation: Hippopotamus Attack

1.a3 e5 2.b3 d5 3.c3 Nf6 4.d3 Nc6 5.e3 Bd6 6.f3 O-O 7.g3

ECO A00

The Formation: Hippopotamus Attack is a chess opening reached after 1.a3 e5 2.b3 d5 3.c3 Nf6 4.d3 Nc6 5.e3 Bd6 6.f3 O-O 7.g3, catalogued under code A00 in the Encyclopaedia of Chess Openings (ECO).

The defining move g3 is chosen by White on move 7.

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Every chess term used here is defined in the chess terms glossary. Browse all opening courses or the full ECO code index.