| Tengen's NES manual credits the original game design to Mark Stephen Pierce and Dave S. Akers. For the NES version it credits the programming to Dave O'Riva, the graphics to Greg Williams, and the music to LX Rudis and Dave O'Riva. | image 3, Creditsimage 3, Creditsimage 3, Creditsimage 3, Creditsimage 3, Credits | Manual |
| Tengen published the NES cartridge without Nintendo's license. Its manual prints "KLAX: TM Atari Games; licensed to Tengen, Inc. ©1990 Tengen, Inc" and refers players to Tengen's game counselors; Tengen's advertisement in Electronic Gaming Monthly's August 1990 issue says Tengen's products are not designed, manufactured, sponsored or endorsed by Nintendo, and that Klax was "Appearing first on the NES", to follow on the Genesis, the TurboGrafx and home computers. Nintendo of America's list of NES games has no entry for Klax. | image 2, inside coverimage 2, inside cover | Manual |
| In the NES manual, Klax is a "tic-tac-tile game": colored tiles tumble down a conveyor belt and the player catches them and arranges them in same-colored lines. A Klax is three or more tiles of the same color in a row, vertical, horizontal or diagonal. The player's paddle moves between five positions at the foot of the conveyor and holds up to five tiles; the A Button flips the top tile into the bin below, Up on the control pad throws the top tile halfway back up the conveyor, and Down speeds the tiles up. There are up to eight colors plus a flashing wild tile that stands for any color. A tile the paddle misses drops and adds to the drop meter, and the game ends when the meter is full. | image 2, Object of the Gameimage 8, p. 5, How to Playimage 8, p. 5, How to Playimage 8, p. 5, How to Playimage 8, p. 5, How to Playimage 8, p. 5, How to Playimage 8, p. 5, How to Playimage 8, p. 5, How to Playimage 9, p. 6, Drop meterimage 9, p. 6, Drop meter | Manual |
| The NES manual describes five types of wave, each set at its start: get a number of Klaxes, a number of diagonal Klaxes, a number of horizontal Klaxes, a number of points, or catch a number of tiles. A warp screen after the start lets the player choose the wave to begin at, and a second player can press Start there to play at the same time. The options let the player turn the drop meter off for wave 1, choose easy, medium or hard, turn ramping on or off, and pick sound effects or music; a Stuff menu holds Blob Ball, which the manual says "has no relationship whatsoever to the rest of KLAX". | image 9, p. 6, How to Complete a Waveimages 9-10, pp. 6-7, How to Complete a Waveimages 9-10, pp. 6-7, How to Complete a Waveimages 9-10, pp. 6-7, How to Complete a Waveimages 9-10, pp. 6-7, How to Complete a Waveimage 4, p. 1, Warp Screenimage 6, p. 3, Options Menuimage 6, p. 3, Options Menuimage 6, p. 3, Blob Ballimage 9, p. 6, How to Complete a Waveimage 4, p. 1, Warp Screenimage 6, p. 3, Options Menuimage 6, p. 3, Options Menuimage 6, p. 3, Blob Ball | Manual |