Whac-A-Mole is an arcade redemption game. A typical Whac-A-Mole machine consists of a large, waist-level cabinet with five holes in its top and a large, soft, black mallet. Each hole contains a single plastic mole and the machinery necessary to move it up and down. Once the game starts, the moles will begin to pop up from their holes at random. The object of the game is to force the individual moles back into their holes by hitting them directly on the head with the mallet, thereby adding to the player's score.
If the player does not strike a mole within a certain time or with enough force, it will eventually sink back into its hole with no score. Although gameplay starts out slow enough for most people to hit all of the moles that rise, it gradually increases in speed, with each mole spending less time above the hole and with more moles outside of their holes at the same time. After a designated time limit, the game ends, regardless of the skill of the player. The final score is based upon the number of moles that the player struck.
In addition to the single-player game described above, there is a multi-player game, most often found at amusement parks. In this version, there is a large bank of individual Whac-A-Mole games linked together, and the goal is to be the first player to reach a designated score, rather than hit the most moles within a certain time. In most versions, striking a mole is worth ten points, and the winner is the first player to reach a score of 150 (i.e. 15 moles). The winner receives a prize (typically a small stuffed animal, which can be traded up for a larger stuffed animal should the player win again).
There are also machines that have very similar gameplay to Whac-A-Mole, however since Whac-a-Mole is a trademark of Bob's Space Racers Inc., they are sold under other names. Whac-a-Mole has also inspired a number of Internet games and Mobile games that are similar in gameplay and strategy.
In the 1990's Bob's Space Racers introduced smaller versions in junior and toddler sizes. Some of the toddler games use A-B-C heads instead of mole heads. The toddler version also has only three mole holes and the difficultly level has been reduced for the younger clientele. In 2004 the company introduced the Whac-a-mole SE (Special Edition) with elaborate graphics and moles wearing hard hats.
Whac-a-mole has been licensed to various companies for production of consumer products. In 1999 Whac-a-mole was introduced as an electronic board game by Toy Biz, now a division of Marvel Entertainment, Inc. In 2004 the game was reintroduced by Hasbro, Inc. Currently there are also versions in cell phones, handheld video, and home video.