The ping to any target at instant speed is relevant, but what makes this card a monster is its ability to subsequently trigger whenever your opponents draw a card outside of the first one each turn, and in formats where this is an everyday matter such as Modern or Legacy, this ability is among the best
Decks With This Card Recent public and tournament decks using Destiny HERO - Destroyer Phoenix Enforcer
not only does it cost less mana than LabMan, but it doesnt require an additional effect to draw a card, and killing it in response rarely interrupts the win since the trigger goes straight to the stack
Based around various mythical creatures of the sea, Mermail Abyssgaios channels the energy of Poseidon himself
Once you try a Dragon Shield sleeve, you'll likely not want to go back to anything else
I totally oppose the idea of not applying an errata to the old werewolves