Centipede

Centipede is an action game originally released in arcades in 1980 by Atari and later ported to numerous home computers and game consoles. The game takes place in an enchanted forest filled with mushrooms and many dangerous insects; players are armed only with a magic wand to defend from the insect attacks. The goal of the game is to earn as high of a score as possible by shooting the various insects and mushrooms.

Gameplay takes place in a mushroom forest with the mushrooms placed randomly at the beginning of the game. Players control a bug blaster which is limited in movement to anywhere in the bottom 5th of the screen. Pressing the fire button causes the bug blaster to fire a shot (only one shot may be on the screen at a time) which can destroy mushrooms or insects. When each level begins, a centipede begins snaking its way from the top of the screen towards the bottom; it will travel left or right until it hits either a mushroom or the edge of the screen at which point it drops a level lower and reverses direction. The centipede is made up of body and head segments; each time a segment is shot, it turns into a mushroom. If one of the body segments is shot, a new head is formed and the centipede is split into two, each one heading in different directions. In addition to the centipede, other insects (which include spiders, fleas, and scorpions) appear from time to time as well. If the players bug blaster is hit by any of these insects a life is lost; the game ends when the players has no remaining lives.

In Centipede the player will encounter the following opponents and obstacles throughout the game:

• The Centipede
  The centipede consists of 12 segments and all segments need to be destroyed to continue to the next level. Centipedes begin at the top of the screen in a progression of 12 different formations; initially, the centipede consists of one head and 11 body segments. In the next wave, there is one head with 10 body segments and one individual head that enters from the sides. The next wave has one head with 9 body segments and two independent heads that enter from the sides. This progression keeps continuing until all 12 segments are independent head segments, and then the pattern repeats. Except for the first level, each wave in the progression needs to be completed twice: once with the centipede moving slowly, and once with it moving fast.
• Fleas
  Fleas first appear on wave 2. They only appear when there aren't many mushrooms in the playfield and fall quickly from the top of the scren towards the bottom leaving new mushrooms as they pass. It takes two shots to destroy a flea; after the first shot they speed up and the second shot destroys them.
• Spiders
  Spiders appear on the left or right side of the screen and travel towards the opposite side. They bounce up and down randomly and move at a 45 degree angle. Any mushrooms they cross over are removed from the playfield. Shooting a spider earns points, and the closer to the spider the player is the more points are earned.
• Scorpions
  Scorpions begin appearing in wave 3. They travel horizontally across the screen and poison any mushrooms in their path. If a centipede hits a poisoned mushroom it will head directly towards the bottom of the screen instead of travelling back and forth.
• Mushrooms
  Mushrooms are randomly placed throughout the playfield and earn points if completely shot. When the player loses a life, any mushrooms that are partially shot are restored to a full mushroom and points are earned. Mushrooms can provide cover for the player or get in the way. When too few mushrooms remain in the playfield fleas will appear to generate more.

Each insect opponent makes a unique sound when on the screen which can provide cues to the player on what types of dangers need to be avoided.

Points are earned for shooting opponents and mushrooms as follows:

• Destroyed mushroom: 1 points
• Restored mushroom: 5 points
• Centipede head segment: 100 points
• Centipede body segment: 10 points
• Spider at close range: 900 points
• Spider at medium range: 600 points
• Spider at far range: 300 points
• Flea: 200 points
• Scorpion: 1,000 points

After 60,000 points are earned fleas start travelling faster and the spider moves in a more restricted space closer to the player. The spider also speeds up after a certain number of points are earned (the amount varies depending on the difficulty setting of the game).