• Please get yourself a copy of The Pragmatic Programmer, and read and reread the section on DRY:

  Don't Repeat Yourself.

  The fetching part of the script should be rolled into a function that handles a given strip, and then called for each of the strips. What you're doing there is a maintenance nightmare.
• How is one to know what $i means? It's not in a loop, so I have no clue unless I look at it throughout the code.
• Your file opening test is meaningless because it can never succeed. || is not the same as or. What you're calling there as

  open PAGE, ">comics.html" || die $!;
  [download]

  is effectively

  open PAGE, (">comics.html" || die $!);
  [download]

  The part in parens will ALWAYS evaluate to ">comics.html". What you want is:

  open PAGE, ">comics.html" or die $!;
  [download]

  which is effectively

  (open PAGE, ">comics.html") or die $!;
  [download]

• If you're using Perl 5.6.0+, avoid the bareword style filehandles, and instead use

  open my $fh, ">", "comics.html" or die $!;
  [download]

The rest of the comments posted are good ones, too.

xoxo,
Andy
--
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