Let's try this again!

my $word = 'abracadabra';
my @list = qw( a b c d e );


my %list = map { $_ => 1 } @list;

foreach (@list) {
   delete $list{$_} if $word =~ s/\Q$_//;
}

@list = keys %list;

print("remaining word: ", $word, "\n");  # raaabra
print("remaining list: ", @list, "\n");  # e
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remaining word: raaabra
remaining list: e
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If you wish to replace all intances of the characters in @list, replace s/\Q$_// with s/\Q$_//g. The output would then be the following for the above snippet:

remaining word: rr
remaining list: e
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