Chess of the position. Weaknesses in the pawn structure, such as isolated, doubled, or backward pawns and , once created, are often permanent. Care must therefore be taken to avoid these weaknesses unless they are compensated by another valuable asset (for example, by the possibility of developing an attack). A chess opening is the group of initial moves of a game (the "opening moves"). Recognized sequences of opening moves are referred to as "openings" and have been given names such as the Ruy Lopez or Sicilian Defense. They are catalogued in reference works such as the "Encyclopaedia of Chess Openings". There
Tactical role-playing game to equip them, change classes, train them, depending on the game. A number of early role-playing video games used a tactical form of combat, such as "Tunnels of Doom" (1982) and "" (1983), as well as "The Dragon and Princess" (1982) and "Bokosuka Wars" (1983), which introduced party-based, tiled combat to America and Japan, respectively. Further, tactical RPGs are descendents of tabletop role-playing games and wargames, such as "Dungeons & Dragons" and "Chainmail", which were mainly tactical in their original form. Nevertheless, much of the development of tactical RPGs has diverged on each side of the Pacific, and the term