The game was originally released by Success in Japan for the Gameboy Advance and Playstation 2 where it went by the title of Zooo. The Playstation 2 version of the game was later released in Europe by the company 505 Games under the title Zoo Puzzle. The games main release however has been on the Nintendo DS where it has been released across Europe, Japan and North America.
The story of Zoo Keeper seems at first extremely simple, involving a zoo keeper and the strict zoo curator who hates the animals of the zoo. After completing zoo keeper mode however, the game tells the story of a man and his wife who had a child and dreamed of creating the worlds biggest zoo. They worked very hard to manage the zoo but the man's wife died and he was filled with great sorrow and believed that his wife had become a victim of his dream. It is revealed that the man is the curator of the zoo and his son is the zoo keeper. He apologizes to his son, saying that he blamed his wife's death on the animals of the zoo, but proclaiming that the zoo would become world-famous.
The games screen involves a grid of tiles representing various animals. Each tile in the grid can be swapped with the tiles above, below and to either side of it. If the tiles are swapped in such a way that a row or column of 3 or more identical tiles is made, the player catches those animals, the player scores points, those tiles disappear and new tiles drop down into their place, otherwise the tiles are swapped back to their original positions. The player gains more points depending on how many tiles they cleared at one and if a new set row or column of 3 or more tiles is made when new tiles drop into position, then this will result in a chain where the player is awarded with additional points and with multiple chains scoring more and more points.
On the left side of the screen the timer can be seen. The timer drains over time and will drain faster or slower depending on the difficulty of the level of the game the player is attempting. The timer is filled every time the player scores points and the more points are scored, the more the timer will be filled, but if this meter runs out they are deemed to have failed the level. On the right side of the screen are the binoculars of which the player can have up to three at a time. When the player uses up one of their binoculars the game points out all the places on the screen where successful moves can be made. Special panels may appear in the place of normal tiles and when selected they clear all of one type of tile from the screen or when put into a row or column of three they give the player a 'REVOLUTION' or 'ILLUSION' bonus which gives the player a large sum of bonus points. In a situation where the player can make no more successful moves the game will change all tiles on the screen and reward the player with bonus points. Each level usually also features a special animal which will give the player double the points if they manage to clear a row of column of them.
The game features 4 different levels of difficulty and leaderboards to record high scores on.
The game includes 4 single player modes and 1 multiplayer mode: Zoo Keeper
This is considered the main mode of the game and involves playing through a number of levels, collecting a specific number of each animal to pass each level, until all the levels are completed and the game ending plays.
This mode involves working your way through a number of levels in a manner similar to the Zoo Keeper mode. However, to complete each level, 100 of any type of animal must be captured. The animals captured on previous levels roll over to the next level and when 100 of any type of animal are collected the counter for that animal resets back to 0.
In this mode there are 10 levels and on each level the zoo keeper receives a random challenge from the curator, e.g. Capture 20 lions, create thirty chains. After each task the player is rewarded or punished (depending on how well they completed their task) by a multiplier or divider being added to their score or by a small increase or deduction of points.
The levels in this mode progress in the same manner as the levels in Zoo Keeper mode do, but the player is only given six minutes to attain the highest score possible and the number of animals required to pass each level is reduced.
This mode lets you play against another player with the game wirelessly (Nintendo DS version only). As you capture more animals your timer increases and theirs decreases. The first person to have their timer hit 0 loses the match and there are 3 matches in each battle. A number of exclusive power-ups also appear in this mode. In addition to the binoculars players can also obtain hearts to restore their timer, buckets to change their opponents animal color and the curator to directly drain their timer.
- There was a bug in the US and Japanese releases of Zoo Keeper which meant that the DS did not go into sleep mode when it was closed. This bug was fixed in the European version.
ZOOKEEPER DX Touch Edition
A re-release emerged for iOS devices which includes the orional Zoo Keeper (renamed as "normal game") and Tokoton modes. High resoultion art assets and online leaderboards have also been added. New features added via free updates have been promised on the game's App Store page.