Meltdown is a 1986 isometric computer game developed by Alligata Software for the Amstrad CPC. There are two English language versions, a 64k version with a little basic speech synthesis and a 128k version featuring much more speech synthesis. A version was also released in French called Le Syndrome.

The player has to navigate three mazes from the 1st floor down to the 3rd floor of a nuclear reactor to prevent a nuclear meltdown. There are eight computer terminals on each floor, the first allowing access to previous floors. Six of the terminals provide access to a different game within a game which the player must win in order to get a password. Once all six passwords have been retrieved the eighth computer allows the player access to an end-of-level game which the player must complete before being allowed access to the next floor. Altogether there are 24 games (three isometric mazes, 18 sub-games and three end-of-level games) which must be completed to win the whole game. The final game is a text-input only robot system for adjusting the control rods of the reactor so it won't explode.