Herald of Secret Streams (Promo Pack) [Ixalan Promos] DP42 when your opponent targets exactly

when your opponent targets exactly 1 face-up "Mermail" monster you control for an attack

(Xyz Materials attached to it also become Xyz Materials on this card

If a "Toon World(s)" you control would be destroyed by card effect

put a +1/+1 counter on the first creature

Set: Collectors' Edition Type: Artifact Rarity: Rare Cost: {2} Time Vault enters the battlefield tapped

Herald of Secret Streams (Promo Pack) [Ixalan Promos] DP42 when your opponent targets exactlySet: Ixalan Promos Type: Creature Merfolk Warrior Rarity: Rare Cost: {3}{U} Creatures you control with +1 +1 counters on them can't be blocked. "You might as well try to stop the waterfall."