Astroblast is an Intellivion shooter which was originally conceived as an Asteroids clone called Meteor!, with a variation of the game called Avalanche that was built to fill up the remaining cartridge space. When Matel made the decision not to release Meteor! because it was too similar to Asteroids, the company changed the code to skip the variant selection screen and go straight to the Avalanche version, which was later renamed Astrosmash.
In Astrosmash, the player controls a laser that is protecting the earth from falling asteroids and invaders.
In this game, the player must aim and use their weapon to destroy asteroids, which will break apart into smaller pieces, which then also need to be destroyed. Enemy saucers, bombs, and missiles heading for Earth also need to be destroyed.
The player's weapon moves across the planet surface at the bottom of the screen to aim and dodge obstacles. It can perform a hyperspace dodge like Asteroids, which will move it to a random position.
The main objective of the game is to destroy objects falling towards the player.
Objects include asteroids, which break apart when shot, small and large white spinners, homing missiles, and UFOs. These asteroids destroy the player’s weapon on collision, and will cause the player to lose points if they hit the planet.
Spinners will cost the player a life if they come in contact with the player or the planet.
Homing missiles move towards the player, and can follow the player even if he warps away. If they hit the ground, the player loses 10 points.
UFOs appear after the player has gained 20,000 points. They float across the screen, rapidly firing missiles at the player.
Astrosmash was also ported to the 2600 under the name Astroblast.