Hangman games with out class

Hangman.rb

@words = %w{spiderman superman powerpuf hangman}
@finish = false
@limit = 8
@win = false

@word = @words[rand(@words.length-1)]
@answer = "_" * @word.length

def guest(answer)
  @limit -=  1
  answer = answer[0..-2]
  if answer == 'exit' || @limit == 0
    @finish = true
    return 
  end 
  if answer.length == 1
    index = 0
    @word.each_char do |w|
      if w == answer
        @answer[index] = answer
      end
      index += 1
    end
  end
  if answer == @word || @answer == @word
    @finish = true
    @win = true
  end
end

until @finish
  puts @answer
  print "#{@limit} Enter your best guest: "
  guest(gets)
end

if @win
  puts "You are the winner"
else
  puts "Bye loser, the answer is #{word}" 
end