Tap

Units in the realm can be tapped as a cost to activate various abilities. A player may also need to tap a unit as a cost related to spells or abilities on other cards. A minion with summoning sickness cannot tap or be tapped to pay costs (but may be tapped directly by other effects, e.g. Grievous Insult). To tap a card, turn a it 90° to the right, from an upright position. Only untapped units in the realm can be tapped.