Steven, Aperture Connoisseur

So long as this creature is untapped, anytime an opponent casts a spell, if you counter it, exile it instead. You may cast spells exiled this way for their converted mana cost. If an ability of a spell or permanent your opponent controls prevents countering, you may instead tap this creature, and create a token copy of that spell.
This creature does not untap at your untap phase.
{2} untap this creature. You cannot activate this ability if you have tapped this creature this turn.