12. (12 points) Fill in each blank grid at the edge with an arrow, the number in the grid indicates the number of arrows pointing to that number, the direction of the arrow can be up, down, left, right, left-up, left-down, right-up, right-down, but each arrow must point to a number, for example, the filling method in Figure 2 is the answer to Figure 1, please fill in the arrows according to this rule in Figure 3, then the number of arrows pointing to the right-down direction is $\qquad$.

【Answer】Solution: According to the analysis of the problem, the arrows in Figure 3 are filled in as follows: there are 2 arrows pointing to the lower right.

Therefore, the answer is: 2.