The closest thing to a global variable are either "magical" variables or punctuation variables.

No. All punctuation variables are global, and some are magical. Not every global is a punctuation variable or magical. $foo is a valid global scalar that goes in foo's stash, just like @foo.

++ vs lbh qrpbqrq guvf hfvat n ge va Crey :)
Nabgure bar vs lbh qvq fb jvgubhg ernqvat n znahny svefg.
-- vs lbh hfrq OFQ pnrfne ;)
    - Whreq