Hello, World! with semi-common characters
Perl 5, 76 bytes



}{${$_=$`x?B?}{?\w$?}{$_=qq{Lg\LLL$&amp;= w$&amp;RLD=}&amp;qq=y}\LLL$&amp;L _$&amp;RLDA=}=$_=\*G


This uses a feature that has been deprecated, but works locally in my terminal (which is version 5.18.2 as noted). In older versions of Perl ?\w? is a synonym for /\w/ which gives me access to regexp matching and I have enough chars for $&amp; (last match) and $` (text preceding last match). I need these to be able to get the O. I generate this be creating a glob reference ($_=\*G which, cast to a scalar, is something like GLOB(0x7ffb728028d0)). Once that's in $_, ?B? will match the B and $` will contain GLO, I can then match against \w$ which would store O in $&amp; which is inserted into the strings that I'm running stringwise-AND to create the rest of the text, the body of the string is lowercased using \L.

Try it online! - uses /\w/ in place of ?\w? as the version of Perl on TIO is too new.



Perl 5, 65 bytes

This is a bit more cheaty as it relies on the filename on TIO (which is .code.tio), so I don't really think this is competing, but I was happy with the result!



}{${$_=$0}{?\w$?}{$_=qq{Lg\LLL$&amp;= w$&amp;RLD=}&amp;qq=y}\LLL$&amp;L _$&amp;RLDA=}


Try it online!