metadata

license: cc0-1.0
pretty_name: Antichess Openings
tags:
  - chess
  - lichess
  - game
  - games
dataset_info:
  features:
    - name: name
      dtype: string
    - name: pgn
      dtype: string
    - name: uci
      dtype: string
    - name: epd
      dtype: string
    - name: result
      dtype: string
  splits:
    - name: train
      num_bytes: 50493
      num_examples: 334
  download_size: 17073
  dataset_size: 50493
configs:
  - config_name: default
    data_files:
      - split: train
        path: data/train-*

Dataset Card for Lichess Antichess Openings

Dataset Description

A list of 334 documented Antichess openings.

Antichess rules

Antichess is an eccentric variant where you lose all your pieces or get stalemated to win. Pieces move the same way they do in standard chess; however, kings lose their royal powers - they cannot castle, and checks are no longer a threat. Since kings have lost their royal powers, pawns may be promoted to kings. Capturing is forced. If you can take a piece, you must. If multiple pieces can be captured, you may choose which piece you capture. To compensate for the nature of Antichess, you will always be given a chance to decide for promotions, even if you have enabled the option to always promote to Queens.

Dataset Creation

The data for this dataset was manually curated by tolius.

Dataset Usage

Using the datasets library:

from datasets import load_dataset

dset = load_dataset("Lichess/antichess-chess-openings", split="train")

Using the pandas library:

import pandas as pd

df = pd.read_parquet("hf://datasets/Lichess/antichess-chess-openings/data/train-00000-of-00001.parquet")

Using the polars library:

import polars as pl

df = pl.read_parquet('hf://datasets/Lichess/antichess-chess-openings/data/train-00000-of-00001.parquet')

Dataset Details

Dataset Sample

One row of the dataset looks like this:

{
 'name': 
 'pgn': 
 'uci': 
 'epd':
}

Dataset Fields

Every row of the dataset contains the following fields:

name: string, the name of the opening in English.
pgn: int, the sequence of moves leading to the opening position. If not unique, the moves are the most common ones leading to that opening.
uci: int, the same moves described by the pgn field in UCI notation.
epd: int, the EPD (FEN without move numbers) of the opening position, en passant field only if legal

Dataset Conventions

Title case is used for opening names.
Names are structured like Opening family: Variation, Subvariation, ..., e.g., Sicilian Defense: Najdorf Variation, English Attack.
The suggested way to classify games is to play moves backwards until a named position is found. To make this work well with common transpositions, multiple entries for a single opening may be added.
However, each name has a unique shortest line. If necessary, a distinguishing move is appended, e.g., King's Gambit Accepted: Schurig Gambit, with Bb5.

Additional Information

To contribute to the dataset, send a PR or open a discussion in the community tab.