The video game crash of 1983 was a worrying time for video game developers and console manufacturers. Many didn't survive long beyond this point. It was caused by too many of the same kind of Pong console on the market and not enough demand. However in the aftermath, there came the new generation of computers and consoles. The NES being one of them.
Klax was released by Tengen, an off shoot of Atari in 1990. It's a port of the arcade game of the same name. It went largely unnoticed in the puzzle crowd, due to it's release in the 1990 era and it nestled between Nintendo's juggernaut's of Tetris and Dr. Mario.
Gameplay for Klax was simple. Coloured tiles come down the conveyor belt and it's up to the player to stack them. Match 3 and they disappear. It's now considered an underrated gem in the NES library and one that's definitely worth a look at after all these years.