gistfile1.rb

  named_scope :victims_for, Proc.new{|attacker|
    {
      :conditions => [
        %{
          (level BETWEEN :low_level AND :high_level) AND
          characters.id NOT IN (
            SELECT fights.victim_id FROM fights WHERE attacker_id = :attacker_id AND winner_id = :attacker_id AND fights.created_at > :time_limit
          ) AND
          characters.id != :attacker_id
        },
        {
          :low_level    => attacker.level,
          :high_level   => attacker.level + 2,
          :attacker_id  => attacker.id,
          :time_limit   => 1.hour.ago
        }
      ],
      :include  => :user
    }
  }