If a monster(s) is Special Summoned from the Deck or Extra Deck by your opponent's activated monster effect, while this card is in your GY (except during the Damage Step): You can Special Summon this card. When a monster effect is activated that includes an effect that Special Summons a monster(s) (Quick Effect): You can banish 1 card from your hand or field; negate that effect, and if you do, destroy that monster. During the End Phase, if this card is currently banished, and was banished this turn: You can return 1 of your other banished monsters to the GY. You can only use each effect of "Derk, Longing for the Blue Skies" once per turn.