my %HoH = (
  Bennie => { deaths => 1, kills => 13 },
  Bob    => { deaths => 12, kills => 15 },
  Jane   => { deaths => 0, kills => 30 },
  mary   => { deaths => 4, kills => 20 },
);

##</code><code>##

$playerHoH{Harry}{deaths} += 4;
$playerHoH{Harry}{kills}  += 20;

##</code><code>##

#!/usr/bin/perl -w
use strict;

my %playerHoH = (
  Bennie => { deaths => 1, kills => 13 },
  Bob    => { deaths => 12, kills => 15 },
  Jane   => { deaths => 0, kills => 30 },
  mary   => { deaths => 4, kills => 20 },
  );
  
$playerHoH{Harry}{deaths} += 4;   
$playerHoH{Harry}{kills}  += 20;
  
foreach my $name (keys %playerHoH)
{
   print "$name ";  #prints: Jane Bob Harry mary Bennie
}
print "\n";

#again Jane Bob mary Bennie must be and are unique.
#the hash forces them to be that way

foreach my $name (keys %playerHoH)
{
    my $hash_ref = $playerHoH{$name};  #the value is a reference
                                       #to another hash!

    foreach my $key (keys %$hash_ref)
    {
       ### these 2 formulations are equivalent and print 
       ### the same thing                             
       print "One way:     $name: $key => $hash_ref->{$key}\n";
       print "Another way: $name: $key => $playerHoH{$name}{$key}\n";
    }
    print "\n";
}
=above prints:
One way:     Jane: deaths => 0
Another way: Jane: deaths => 0
One way:     Jane: kills => 30
Another way: Jane: kills => 30

One way:     Bob: deaths => 12
Another way: Bob: deaths => 12
One way:     Bob: kills => 15
Another way: Bob: kills => 15

One way:     Harry: deaths => 4
Another way: Harry: deaths => 4
One way:     Harry: kills => 20
Another way: Harry: kills => 20

One way:     mary: deaths => 4
Another way: mary: deaths => 4
One way:     mary: kills => 20
Another way: mary: kills => 20

One way:     Bennie: deaths => 1
Another way: Bennie: deaths => 1
One way:     Bennie: kills => 13
Another way: Bennie: kills => 13
=cut