Editing Asteroids (video game) (section)

==Gameplay==
[[Image:Asteroi1.png|thumb|left|A ship is surrounded by asteroids and a saucer.]]
The objective of ''Asteroids'' is to destroy asteroids and saucers. The player controls a triangular [[spacecraft|ship]] that can rotate left and right, fire shots straight forward, and thrust forward.<ref name="WiredEdLogg">{{cite magazine |url=https://www.wired.com/gamelife/2011/11/ed-logg-pioneer-award/ |author=Chris Kohler |title=Asteroids Designer Ed Logg Honored With Pioneer Award |magazine=[[Wired (magazine)|Wired]] |publisher=[[Condé Nast Publications]] |date=November 17, 2011 |access-date=December 28, 2013 |archive-url=https://web.archive.org/web/20131208141237/http://www.wired.com/gamelife/2011/11/ed-logg-pioneer-award/ |archive-date=December 8, 2013 |url-status=live |df=mdy-all}}</ref> Once the ship begins moving in a direction, it will continue in that direction for a time without player intervention unless the player applies thrust in a different direction. The ship eventually comes to a stop when not thrusting. The player can also send the ship into hyperspace, causing it to disappear and reappear in a random location on the screen, at the risk of self-destructing or appearing on top of an asteroid.<ref name="RetroGamerAsteroids">{{cite magazine |magazine=[[Retro Gamer]] |issue=68 |publisher=[[Imagine Publishing]] |year=2009 |url=http://www.rawbw.com/~delman/pdf/making_of_Asteroids.pdf |title=The Making of Asteroids |access-date=December 18, 2013 |url-status=dead |archive-url=https://web.archive.org/web/20131219041721/http://www.rawbw.com/~delman/pdf/making_of_Asteroids.pdf |archive-date=December 19, 2013 |df=mdy-all}}</ref>

Each level starts with multiple large asteroids drifting across the screen. Objects [[Wraparound (video games)|wrap around screen edges]]; an asteroid that drifts off the top edge of the screen reappears at the bottom and continues moving in the same direction.<ref name="RulesOfPlay">{{cite book |last1=Salen |first1=Katie |last2=Zimmerman |first2=Eric |title=Rules of Play: Game Design Fundamentals |publisher=MIT Press |year=2004 |isbn=0-262-24045-9 |name-list-style=amp}}</ref> As the player shoots asteroids, they break into smaller asteroids that move faster and are more difficult to hit. Smaller asteroids are also worth more points. Two flying saucers appear periodically on the screen; the "big saucer" shoots randomly and poorly, while the "small saucer" fires frequently at the ship. After reaching a score of 40,000, only the small saucer appears. As the player's score increases, the angle range of the shots from the small saucer diminishes until the saucer fires extremely accurately.<ref name="EdgeAsteroids">{{cite magazine |url=http://www.edge-online.com/features/making-asteroids/ |magazine=[[Edge (magazine)|Edge]] |issue=117 |title=The Making of Asteroids |author=Edge Staff |publisher=[[Future plc]] |access-date=January 4, 2014 |archive-url=https://web.archive.org/web/20140104211104/http://www.edge-online.com/features/making-asteroids/ |archive-date=January 4, 2014 |url-status=dead |df=mdy-all}}</ref> Once the screen has been cleared of all asteroids and flying saucers, a new set of large asteroids appears, thus starting the next level. The game gets harder as the number of asteroids increases until after the score reaches a range between 40,000 and 60,000.<ref>{{cite book |last1=Bjork |first1=Staffan |last2=Holopainen |first2=Jussi |title=Patterns in Game Design |publisher=Charles River Media |year=2005 |page=60 |isbn=1-58450-354-8 |name-list-style=amp}}</ref> The player starts with 3–5 lives upon game start and gains an extra life per 10,000 points.<ref name="EsquireAsteroids">{{Cite magazine | url=http://www.gamearchive.com/General/Articles/ClassicNews/1981/Esquire2-81-pg62.htm | magazine=[[Esquire (magazine)|Esquire]] | volume=2 | issue=81 | title=Invasion of the Asteroids | author=David Owen | publisher=[[Hearst Corporation]] |archive-url = https://web.archive.org/web/20080622053948/http://www.gamearchive.com/General/Articles/ClassicNews/1981/Esquire2-81-pg62.htm |archive-date=June 22, 2008}}</ref> Play continues to the last ship lost, which ends the game. The machine "turns over" at 99,990 points, which is the maximum high score that can be achieved.

===Lurking exploit===
In the original game design, saucers were supposed to begin shooting as soon as they appeared, but this was changed.<ref name="EdgeAsteroids"/>  Additionally, saucers can only aim at the player's ship on-screen; they are not capable of aiming across a screen boundary. These behaviors allow a "lurking" strategy, in which the player stays near the edge of the screen opposite the saucer. By keeping just one or two rocks in play, a player can shoot across the boundary and destroy saucers to accumulate points indefinitely with little risk of being destroyed.<ref name="EsquireAsteroids"/><ref>{{Cite news |url=https://news.google.com/newspapers?nid=2206&dat=19820319&id=0IEmAAAAIBAJ&pg=2751,2833371 |newspaper=The Miami News |title=Beating the Video Games: Lurking on an Asteroid |author=Michael Blanchet |date=March 19, 1982 |access-date=January 4, 2014 }}{{Dead link|date=August 2024 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> Arcade operators began to complain about losing revenue due to this [[Video game exploit|exploit]]. In response, Atari issued a patched [[EPROM]] and, due to the impact of this exploit, Atari (and other companies) changed their development and testing policies to try to prevent future games from having such exploits.<ref name="EdgeAsteroids"/>