Ruy Lopez, Exchange Variation Ruy Lopez, Exchange Variation The Exchange Variation of the Ruy Lopez is a chess opening that begins with the moves: Black may recapture on c6 with either pawn; although 4...bxc6 is playable, 4...dxc6 is almost always chosen at master level. Black has gained the at the cost of a weakened pawn structure, due to his doubled pawns on c6 and c7. White aims to reach an endgame in which he has the superior pawn structure, which may become an important factor. Thus, Black is compelled to strive for an active position, generally avoiding piece exchanges. The variation was introduced into
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