Hippopotamus Defense basics by Andrew Martin

Recently, during the sixth round of the Reykjavik Open 2026, a fascinating clash took place between two very different chess personalities. British rising star Bodhana Sivanandan faced legendary commentator and creative opening specialist Simon Williams.

From Williams’ perspective, the matchup posed an interesting challenge with the black pieces. Bodhana has repeatedly demonstrated a calm, positional style reminiscent of José Raúl Capablanca, making wild gambits and offbeat attacking experiments a risky choice, even for the adventurous Ginger GM. Instead, Williams relied on the Hippopotamus Defense, an opening built around a deceptively simple setup that often invites White to overextend. Once White pushes too aggressively beyond the fifth rank, the position can suddenly become dangerous.

Not long ago, renowned Andrew Martin released a ChessBase training course dedicated to this unusual system. The game offers the perfect opportunity to dive deeper into the ideas behind the Hippopotamus Defense through Martin’s commentary and perhaps discover a powerful surprise weapon for future games.

In the video, Andrew Martin explains the fundamental ideas behind the Hippopotamus Defense through a different illustrative game, demonstrating just how brutal and devastating the setup can become once an opponent oversteps the boundary and crosses the line.

The Hippopotamus system of defence

What is the Hippopotamus system of defence? The idea is that, at the beginning of the game, Black develops within his own first three ranks. He constructs a solid, flexible and hopefully stable position, awaiting events. At the right moment, he will strik

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