To solve this expression, we need to follow the order of operations (PEMDAS/BODMAS).

First, let's simplify the exponentiation:

-16^2 = (-16)(-16) = 256
2^6 = 2 * 2 * 2 * 2 * 2 * 2 = 64

Now, let's substitute these values back into the expression:

256 * 64 / (-16^4 + 12^2 - 12)

Next, let's simplify the remaining exponentiation:

-16^4 = (-16)(-16)(-16)(-16) = 65,536
12^2 = 12 * 12 = 144

Substituting these values back into the expression:

256 * 64 / (65,536 + 144 - 12)

Now, let's simplify the addition and subtraction:

65,536 + 144 - 12 = 65,668

Substituting this value back into the expression:

256 * 64 / 65,668

Finally, let's perform the multiplication and division:

256 * 64 = 16,384
16,384 / 65,668 ≈ 0.2499

Therefore, -16^2.2^6:-16^4+12^2-12 is approximately equal to 0.2499.