Parton gives several variations, although Decimal Rettah is "possibly the earlier version and arguably the better" . In Absolute Rettah chess, only a rettah may capture a rettah. (So a successful tactic involves attacking a rettah with a piece guarded by one's own rettah.) In Giveaway Rettah, Decimal or Absolute Rettah are played according to Suicide chess rules. In Rettah chess (one rettah; pawns move only one step forward) and Double Rettah chess (two rettahs; no forced capture; win by checkmating a rettah), play is on a regular 8×8 board.