Kaboom! is a single-screen action game, where the player catches bombs in a series of three buckets. With a gameplay style somewhat similar to Breakout, the player uses a paddle (2600 version) or joystick (5200 version) to control the action.
Gameplay takes place on a single screen. The Mad Bomber, at the top of the screen glides left and right while dropping bombs. The player controls a series of three buckets, which are used to catch the bombs before they land at the bottom of the screen. As gameplay progresses, the Mad Bomber moves and drops bombs more rapidly, increasing difficulty. Points are scored on a sliding scale; the more groups of bombs caught, the more points are awarded - 8 groups giving the maximum multiplier. Each bomb group comes faster, and has more bombs than the prior.
The difficulty switches control the width of the buckets. The 'B' level difficulty decreases the bucket size to less than half of the 'A' level difficulty. The difficulty does not affect scoring.
If the player misses a bomb, the score multiplier is reset, and the player loses a bucket, increasing the challenge on subsequent attempts. Gameplay resumes one bomb set prior to the current bomb set, but with half as many bombs to catch. When all buckets are gone, the game is over. Scoring 1000 points earns the player a new bucket, with a maximum of three earned buckets. Earned buckets may not be stockpiled; a player must earn 1000 points subsequent to losing a bucket to gain a new one. Because missed bombs lower the difficulty, a high level strategy is to purposely miss a bomb around the 900 mark, if successful the player will be easily able to regain an extra bucked while at the same time slowing the onslaught of bombs.
The Atari 2600 version of Kaboom! features 2-player alternating play, with independent difficulty selection. The 5200 version additionally supports a mode whereby players alternate between controlling the buckets, and the Mad Bomber.
Like all Activision releases of this era, the box, manual and cartridge label all feature the name of the designer of that particular game. In this case, Larry Kaplan. Additionally, Larry Kaplan provided several gameplay tips at the back of the instruction manual.
The mad bomber has a "sad face" while dropping bombs, but a "happy face" if one gets by the player. A score of 10,000 points leads to an easter-egg: a surprised face, regardless of the action.
As with many Activision games, a patch was available for excellent gameplay. Providing activision with a photograph of a score of 3000 or better would get that player a free "Bucket Brigade" patch.
Activision released an LCD keychain version of the game in the early 1990s.