Colle & Hippo

Repertoire trainer

The Triangle
& the Swamp

Forty-seven lines, from game scores, book recommendations and the opening database. The Colle as White, the Hippopotamus as Black. Learn them, then let the trainer decide which position you have earned the right to forget.

0Untouched
0Solid
0Due now
0Today
Where each line comes from. Every line carries a tag, and the tag is the claim.
game
A real game score, checked move for move against its sources.
book
A published recommendation, cited in the note.
eco
A named variation, taken verbatim from lichess-org/chess-openings (CC0).
theory
Documented theory, assembled here.
model synthetic
Written for this trainer: legal and thematic, but nobody played them and no book prints them.
Tactics are real positions from real games, filtered out of the lichess puzzle database (CC0) and each linked back to its puzzle page. Opening names come from the same CC0 data set. Piece graphics are Colin M. L. Burnett's standard set, CC BY-SA 3.0, via the lichess repository; board colours are the lichess and chess.com defaults. Legality comes from a move generator written for this app and checked against the standard perft positions, and every move of every line and puzzle here was replayed through it. It is not an engine: it knows what is legal, never what is good.
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Masters database
Notation
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0Seen
0%Accuracy
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