Note: This is a total rewrite to focus on the most applicable solutions.
The simplest solution is probably the following (shown for row 1):
This relies on your description that the only exception to all blanks would be a "Y". This counts Y's. A count of zero is treated as
false, which produces the word "Blank" as output (you can make that anything you want). Any count of 1 or more Y's is treated as
true, and outputs null (an empty cell; it's entered as a pair of double-quotes with nothing between them).
Another way to do this is to look for the blank cells rather than the filled cells:
There are 13 columns in the range A:M. This counts how many are blank. If all 13 are blank, the row is blank.
Note: In either case, you enter the formula once in column N and then just copy it or drag it to fill the results cells as needed. BTW, these will both work in Excel as well as Calc.