|
Crossfire is an Apple II video game created by Jay Sullivan, published by Sierra On-Line in . It was ported to the Atari 8-bit family, VIC-20, and Commodore 64. A cartridge version of ''Crossfire'' was a launch title for the IBM PCjr, announced in late 1983. ==Gameplay== In ''Crossfire'', the player uses the IJKL keys on the keyboard to move and ESDF to shoot left, right, up, and down among an array of blocks, avoiding incoming fire and dispatching enemies. The playing area consists of 42 blocks (7 rows by 6 columns), through which there are six vertical alleys, five horizontal alleys, and 30 intersections. The player can move and fire in any direction, but can only stop in intersections. On e.g. the Commodore 64 port, the game optionally be played with joystick, but this is harder to control than using the keyboard. Along the left, right and top sides of the playing area are 16 pockets, each of which releases four enemies. These enemies emerge and move among the blocks, firing at and attempting to collide with the player. The four types of enemies differ only in appearance, not in power or behavior. On Apple II the first enemies are small, bluish, and diamond-shaped (worth 10 points); the second resemble scarabs (20 points); the third are orange with blue legs (40 points); the fourth are silver and diamond-shaped (80 points). Ports of the game, such as Commodore 64, have different enemy graphics. Like the player, the enemies can move and fire in any direction, but are not as fast. Unlike the player, they never run out of ammunition. The player advances a level when all enemies are destroyed. Within four blocks near the middle of the playing area are four orange, spindle-shaped bonus items. Once the player has fired 12 times (after the beginning of the level or after collecting the previous bonus) the item emerges from its block and becomes accessible. If it has not been collected after five further shots, it goes back into its block, and no further bonus items will appear in that level. Capturing the bonus items grants 100, 200, 400 and 800 points. The player can fire only a limited number of shots before having to reload. In early rounds this number is around 30, but drops by five for each level progressed, until the player can fire only 15 shots. When the player has 10 shots remaining, a cluster of four pulsing white dots appears at the opposite point of the grid from the player. This cluster marks where the player needs to go to reload. A central gameplay mechanic is that the player can only fire one bullet at a time, and can only fire the next bullet once the previous bullet has hit an enemy or gone off the screen. Play begins with three ships; an extra one is awarded every 5,000 points. The game ends when the player is out of ships; if the player never runs out of ships, the game will continue indefinitely. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Crossfire (1981 video game)」の詳細全文を読む スポンサード リンク
|