The Grand Spellbook Tower

Once per turn, during your Standby Phase, if you have a Spellcaster-Type monster on your side of the field or in your Graveyard: You can return 1 "Spellbook" Spell Card from your Graveyard to the bottom of your Deck, except "The Grand Spellbook Tower", then draw 1 card. When this card is destroyed by your opponent's card and sent to the Graveyard: You can Special Summon 1 Spellcaster-Type monster from your hand or Deck whose Level is less than or equal to the number of "Spellbook" Spell Cards in your Graveyard.