B8

Meta Rules
Meta #32 If conditions are such that the card cannot be played this battle unless the opponent performs some action, then the card must be placed or discarded as unusable. If the player holds cards that can create the situation by which the card would be playable, then it can be kept in hand.

Meta #153 Specials which can make other cards (Specials, Power cards, etc.) usable allow you to keep those unusable cards in hand during the discard phase. The Special to make them usable must be available (e.g., Placed, in Hand, available through a specific draw - not through a random draw).