Description: If this card is sent to the GY as Link Material for the Link Summon of a DARK monster: You can Special Summon this card in Attack Position to your zone that Link Monster points to, but it cannot be used as Link Material. If this card is destroyed, or banished, by the activated effect of a Link Monster: Draw 1 card. You can only use each effect of "Triggering Wurm" once per turn.
