Thalia, Guardian of Thraben

Oracle Text

First strike

Noncreature spells cost 1 more to cast.

Card Rulings

1/22/2011 The ability affects each spell that's not a creature spell, including your own.
1/22/2011 The ability affects the total cost of each noncreature spell, but it doesn't change that spell's mana cost or converted mana cost.
1/22/2011 When determining a spell's total cost, effects that increase the cost are applied before effects that reduce the cost.