\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/
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with capturing parens to capture these two characters:

/(..)\z/
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or maybe like this:

/(.{2})\z/
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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/;
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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.