This is a fantastic card for many mystics, especially later in the campaign when they might have picked up some trauma and when there are treacheries/enemies that dish out tons of horror. The two symbols is just what you need, since you use it for almost everything through spells. Agnes in particular loves this, since any horror healed off her allows her to deal more damage, and she is more likely to succeed by 2 with her innate 5 willpower + potential boosts. Even better if you chose to include Arcane Research, since the two mental trauma means this card will be live from the very start.