Until end of turn, your hero gains "Whenever you draw a card this action phase, deal 1 arcane damage to any target". (Brainstorm itself does not have an arcane damage effect. It is not modified by arcane damage modifiers.)
Until end of turn, your hero gains "Whenever you draw a card this action phase, deal 1 arcane damage to any target". (Brainstorm itself does not have an arcane damage effect. It is not modified by arcane damage modifiers.)