\Z is an assertion or anchor, it matches
at a position (the end of the string, or in front of a final newline — you probably ment to use
\z instead), but it doesn't match anything with a nonzero length. And then you're asking, with
{2}, to match it twice... or rather, you're asking it
not to match. It's all very confusing. I'm sure you're feeling that way... :)
What you should try to match, is two characters, followed by the end of the string. I can do it like this:
/..\z/
with capturing parens to capture these two characters:
/(..)\z/
or maybe like this:
/(.{2})\z/
After it matches, you can read the captured value out of $1, or you can put it directly into a variable like this:
($sight) = /(.{2})\z/;
which will leave
$sight undefined if it fails to match. Note the parens on the left, it tells the assignment operator
= it's being called in list context, so the regexp returns a list of captures, and it assigns the first item in the returned list to the variable
$sight.