How come it's saying undefined local variable withing my class? The variable is an array and its defined so now im lost.

class Pokemon

  @chosen_6 = ["Pikachu","Butterfree","pidgeotoo","bulbasaur","charmander","squirtle"] 
  @chosen_6v2 =["Staryu","garadose","starmii","psyduck","politoad","togepi"]
  @chosen_6v3 =["geodude","onix","vulpix","zubat","crok","idk"]

  def initialize(trainers,badges) 
    @trainers = trainers 
    @badges = badges
  end

  def trainers
      case @trainers 
      when "Ash","ash"
      puts "hi"
      end
  end

  def bio
      puts "Now loading bio of.......#{@trainers}"
      case @trainers
      when "ash","Ash"
      puts "Ash ketchum is a pokemon trainer who one day dreams of being pokemon master."
      when "Misty","misty"
      puts "Misty is the curealn city gym leader and is a real bitch"
      when "Brock","brock"
      puts "Brocks a loser" 
      end
  end

  def badges
      puts "#{@trainers} has this many badges #{@badges}."
      if @badges < 8
      puts "Oh im sorry #{trainers} does not have enough badges to enter league."
      else 
      puts "Alright you have enough to enter."
      end
  end 

  def pokemons 
    case @trainers 
    when "Ash","ash" 
      puts "Ash's pokemon are #{@chosen_6}" 
    when "Misty","misty" 
      puts "Misty calls #{@chosen_6v2}" 
    when "Brock","brock" 
      puts "Brock's pokemon are #{@chosen_6v3}"
    end 
  end 
end

ash = Pokemon.new("ash",8)

ash.trainers 
ash.bio 
ash.pokemons
ash.badges 
puts "--------------------------" 
misty = Pokemon.new("misty\n",0) 
misty.bio 
misty.pokemons 
misty.badges
puts"---------------------------" 
brock = Pokemon.new("Brock",0) 
brock.bio 
brock.pokemons 
brock.badges

  def initialize(trainers,badges) 
    @trainers = trainers 
    @badges = badges
    @chosen_6 = ["Pikachu","Butterfree","pidgeotoo","bulbasaur","charmander","squirtle"] 
    @chosen_6v2 =["Staryu","garadose","starmii","psyduck","politoad","togepi"]
    @chosen_6v3 =["geodude","onix","vulpix","zubat","crok","idk"]
  end