Skilled Dark Magician (SDSC-EN007) - Structure Deck: Spellcaster's Command Unlimited

Each time you or your opponent activates 1 Spell Card, put 1 Spell Counter on this card (max. 3). By Tributing this card with 3 Spell Counters on it, Special Summon 1 "Dark Magician" from your hand, Deck, or Graveyard.