12. There are five cages arranged in a row, labeled from left to right as shown in Table 1.
Table 1
\begin{tabular}{|c|c|c|c|c|}
\hline \begin{tabular}{c} 
Red \\
Wolf
\end{tabular} & \begin{tabular}{c} 
Silver \\
Lion
\end{tabular} & \begin{tabular}{c} 
Brown \\
Fox
\end{tabular} & \begin{tabular}{c} 
White \\
Cow
\end{tabular} & \begin{tabular}{c} 
Gray \\
Horse
\end{tabular} \\
\hline
\end{tabular}

Each cage contains exactly one animal, satisfying the following conditions:
(1) These five animals are indeed a wolf, a lion, a fox, a cow, and a horse, and their colors are indeed red, silver, brown, white, and gray;
(2) None of the labels indicate the correct color or animal inside the cage;
(3) Each animal is not in the cage labeled with its color or type, nor is it in the adjacent cage.

If the horse is not in the middle cage, then the color of the horse is . $\qquad$
12. White.

Consider the labels on the middle three cages. From (3), we know that the lion, fox, and ox are not in the middle cages. Since the horse is also not in the middle cages, it can only be the wolf inside.

Since the first label is “Red · Wolf,” the wolf is not red. From (3), we also know it is not silver, brown, or white. Therefore, the wolf is gray.

The ox and the horse cannot be in the 4th or 5th cages, so these two cages must contain the badger and the fox.

Noting that the fox cannot be adjacent to the 3rd cage, it must be in the 5th cage, and the lion must be in the 4th cage.

Since the second label is “Silver · Lion,” the lion is not silver. From (3), we also know it is not brown, white, or gray. Therefore, the badger is red.

Since the third label is “Brown · Fox,” the fox is not brown. From (3), we also know it is not gray or white. Since the badger is red, the fox must be silver.

Since the fourth label is “White · Ox,” the ox is not white, so it must be brown and is in the first cage. Therefore, the second cage can only be the horse, and the horse is white.