Blasteroids is the fourth Asteroids game in the Asteroids Series. Its a Multidirectional Shooters like all the other Asteroids games. It was developed by Atari (which later became Midway Games West) and published in 1987 by Image Works. It was released on many formats after the Arcade in 1989 which include: Amiga, Amstrad CPC, Atari ST, Commodore 64/Commodore 128, MSX, MS-DOS PC, ZX Spectrum.
The gameplay for the game is basically the same as for the original; the player (or players in case of a 2-player game) controls a spaceship viewed from "above" in a 2D representation of space, by rotating the ship, and using thrust to give the ship momentum. To slow down or completely stop moving, the player has to rotate the ship to face the direction it came from, and generate the right amount of thrust to nullify its momentum. The ship has a limited amount of fuel to generate thrust with. This fuel comes in the form of "Energy" that is also used for the ship's Shields which protect it against collisions and enemy fire. Once all Energy is gone, the player's ship is destroyed. The ship can shoot to destroy asteroids and enemy ships. The ship can also be transformed at will into 3 different versions, namely the "Speeder", the fastest version, the "Fighter", which has the most firepower, and the "Warrior", which has extra armour.
At the start of the game, the player is in a screen with 4 "Warps" indicating the game's difficulty: Easy, Medium, Hard, and Expert. Flying through any of the Warps starts the game with that difficulty. Each Warp has several "Galaxies", each with 9 or 16 "Sectors" (levels), depending on difficulty. Once a Sector is completed by destroying all the asteroids, an "Exit Portal" (another Warp) appears to lead the player to the "Galactic Map" screen. Similarly to the difficulty screen, the player can here choose which Sector to visit next. Completed and empty Sectors can be revisited, but since this costs Energy, this is pointless. Sectors that are currently out of range are marked with a "?".
Each level (called "Sector" in the game) consists of only the visible screen. The top and bottom of the screen are connected, as are the left and right side of the screen, meaning if anything leaves the screen, it will appear again on the opposite side. (A Sector can be thought of as the surface of a torus laid out flat.)
The object of the game is to destroy all the asteroids which have a set speed at which they fly through the Sector. Asteroids come in varying sizes, and when shot, larger asteroids break into multiple smaller ones. Only shooting the smallest ones will actually remove them from the Sector. Asteroids also come in different types. Normal asteroids don't contain anything, but red asteroids can contain power-ups in the form of Power Crystals that are released by completely destroying asteroids. Crystals decay over time. Popcorn Asteroids require several hits, which expands their size, and eventually makes them stop spinning. They can't be destroyed, but stopping them is enough to finish each Sector. Egg asteroids contain leeches which home in onto the user's ship and suck out its energy. They can be shot and destroyed. Finally there are Seeker asteroids which home in on the player's ship.
Besides asteroids, there are different enemy ships trying to shoot the player, that leave equipment in the form of power-ups when destroyed.
There are different kinds of equipment:
- Shields - give limited amount of protection
- Blasters - gives the ship double shots
- Extra Shot Power - allows shots to penetrate everything
- Ripstar - causes the ship to spin furiously, firing in all directions
- Extra Fuel Capacity - increases fuel capacity
- Booster - increases movement speed for all ship forms
- Crystal Magnet - attracts loose Power Crystals to the ship
- Cloak - ship turns invisible to enemies