What is the range of the function $f(x)$ defined by $f(x)=\left\{\begin{array}{ll}-1, & x<-2 \\ x^{2}-4, & -2 \leq x<0 \\ x-4, & 0 \leq x \leq 4 \\ 0, & x>4\end{array}\right.$

Step 1 ：Find the range of the function for each interval:

Step 2 ：Interval 1: \(x < -2\), \(f(x) = -1\), range is \(-1\)

Step 3 ：Interval 2: \(-2 \leq x < 0\), \(f(x) = x^2 - 4\), range is \([-4, 0]\)

Step 4 ：Interval 3: \(0 \leq x \leq 4\), \(f(x) = x - 4\), range is \([-4, 0]\)

Step 5 ：Interval 4: \(x > 4\), \(f(x) = 0\), range is \(0\)

Step 6 ：Combine the ranges from each interval to find the overall range of the function: \([-4, 0]\)

Step 7 ：\(\boxed{[-4, 0]}\)