Source: Wikipedia, "Crazy Kong", available under the CC-BY-SA License.
Crazy Kong is an arcade game created by Falcon, released in 1981 and is similar to Nintendo's Donkey Kong. Although commonly mistaken as a bootleg, the game is officially licensed for non-U.S. markets and is based on different hardware. The game retains all of the gameplay elements of Donkey Kong, but has all of the graphics redrawn and re-colorized. Crazy Kong is also known as the portmanteau Congorilla, Crazy Kong Part II, and Monkey Donkey.
There are two versions of the original Crazy Kong and Crazy Kong Part II; the differences of which are in minor cinematic artifacts and bugs, color palette choices and minor gameplay differences. Crazy Kong Part I shows no copyright or company name on the title screen. Crazy Kong (parts I and II) runs on modified Crazy Climber hardware. In addition there are other versions of the game that run on Scramble, Jeutel, Orca, and Alca hardware. The official versions of game came in two different stand up cabinets that featured a large and angry, rather than comic, ape embedded in the artwork.
The title screen of the game features either the text "Crazy Kong" or "Monkey Donkey" written in girders dependent upon which version is running. There is no graphic of Kong on the main screen. No copyright, just the year '1981'. The girder text does not flash different colours for a few seconds before stopping, as in Donkey Kong.
The color palette has been almost completely changed; Part I and Part II have different palette choices.
Most of the game graphics have been re-drawn; while Donkey Kong looks almost the same from a side view, his frontal appearance is noticeably different when he opens his mouth; he is taller and much more fierce looking.
Many animations are removed. For example in the classic first level, barrels appear from Crazy Kong, as opposed to showing the rolling animations. He is locked in the horizontal roll animation but does not reach for the other barrels or move when rolling barrels vertically. Frames of animation are also removed at the beginning and ending of each level.
The sound effects are altered and are generally more crude sounding. The background humming music is removed and Jumpman is given a digital sample "hugggh" sound when jumping. A lot of the in game sounds such as the "Kong chest beating" can also be found in the game Crazy Climber on those versions that run on its proprietary hardware.
The game is considered slightly more difficult than Donkey Kong because the collision detection is less forgiving and the game is slightly faster.