XOR -TizzyT

        public enum Alignment { Left = 0, Right = 1 }
        public static byte[] Xor(this byte[] arr1, byte[] arr2, Alignment alignment = Alignment.Left)
        {
            if (arr1.Length < arr2.Length) { byte[] ba = arr1; arr1 = arr2; arr2 = ba; }
            byte[] result = new byte[arr1.Length];
            if (alignment == Alignment.Left) Array.Copy(arr2, 0, result, 0, arr2.Length);
            else Array.Copy(arr2, 0, result, arr1.Length - arr2.Length, arr2.Length);
            for (int i = 0; i < arr1.Length; i++) result[i] ^= arr1[i];
            return result;
        }