I find a lookup table is the way to go for these situations. 
#!/usr/bin/perl

use strict;
use warnings;

my $beholder_default = 'beholder';

my $param = get_param();

my @keys = (
  'beholder', 'deathkiss', 'eye of the deep',
  'gauth', 'spectator', 'undead', 'hive mother',
  'director', 'examiner', 'lensman', 'watcher'
);

my %lookup = (
  'beholder' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'death kiss' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'eye of the deep' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'gauth' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'spectator' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'undead' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'hive mother' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'director' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'examiner' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 21,
  },
  'lensman' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 25,
  },
  'overseer' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 25,
  },
  'watcher' => {
    book => 'Monstrous Manual',
    beholder => 'beholder',
    page => 25,
  },
);

my $key;
if ($param){
  $key = $beholder_default;
}
else{
  $key = $keys[rand @keys];
}

my $beholder = $lookup{$key}{beholder};
my $book = $lookup{$key}{book};
my $page = $lookup{$key}{page};

print "beholder: $beholder\n";
print "book: $book\n";
print "page: $page\n";


sub get_param {
  # get your input from somewhere
  my $param = undef;
  return $param;
}

[download]
Ah, I didn't see your update before I posted this.

In reply to Re^4: Creating a random generator by wfsp
in thread Creating a random generator by Lady_Aleena

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