Zoo Keeper (Nintendo DS)/Gameplay

The game play follows the basic rules of games like Diamond Mine. You are presented with a screen full of square rows and columns of items, as in a bin. The basic layout would look something like:

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 * H B M G A B H E |
 * M M A B P G M P |
 * H B M P P A P G |
 * A M P G B M A G |
 * G B E H A H G A |
 * P E G A B G P H |
 * A H E H B A E H |

A = Alligator  B = Bunny    E = Elephant   G = Giraffe H = Hippo      M = Monkey   P = Panda

Any move in the game consists of swapping the positions of two adjacent items, in either the horizontal or vertical directions (no diagonals). Every move must result in at least one row or column of at least three identical items being formed. No other move is allowed (trying to make an invalid move is not penalized). Once the swap has been made, any rows and columns of at least three identical items are removed from the playing area. The remaining items are pushed downwards to not leave any empty space, and random items are generated at the top of the rows to fill up the board.

The board is then scanned again (before the player can make another move) for rows or columns of at least three identical items. These are removed again, and the items pushed downwards to pack the playing area, with random pieces brought in at the top. This process continues until there are no rows or columns to be eliminated, at which point the player can make their next move.