Chess opening are so complex and theoretical that amateur players will have trouble understanding them. An example is the Perenyi Attack of the Sicilian Defense (see diagram) which yields an immensely complicated and tactical position that even strong players have difficulty handling, and that is beyond the comprehension of most amateurs. Major changes in the rules of chess in the late fifteenth century increased the speed of the game, consequently emphasizing the importance of opening study. Thus, early chess books, such as the 1497 text of Luis Ramirez de Lucena, present opening analysis, as does Pedro Damiano (1512), and Ruy López de
Army Moves to a review in Zzap!. However, it received mixed reviews from ZX Spectrum magazines and was successful enough in Spain to spawn two follow-ups, Navy Moves in 1988 and Arctic Moves in 1995. The latter appeared only for the PC platform, and it included the first two chapters of the series, playable through a ZX Spectrum emulator, as an extra. A fourth entry in the series, "Desert Moves" was announced at the end of the game Arctic Moves, but never appeared. The game music in non-Spanish versions is based on the Colonel Bogey March. Army Moves Army Moves is a