Veiled Serpent

An enchantment that does nothing until an opponent obliges, then springs into a 4/4 Serpent the instant they cast a spell: the trigger condition is the whole engine. It rewards a passive posture, a player content to hold up nothing while baiting the other side into committing first, and converts that patience into a wall stout enough to trade up against most early threats. The attack restriction settles what kind of card it is: it can only swing where the defending player controls an Island, so against everyone outside the blue mirror it stays planted on defense rather than becoming a clock. Reactive permanents that idle until an opponent cooperates have an obvious flaw, though: in the games where the other side sits on their own hand, the card just rots. Cycling answers that. For two mana it sheds itself into a fresh card, so a dead matchup never means a dead slot, only a cantrip you fire when the Serpent has nothing to wake up for. That pairing of a conditional body with a built-in escape hatch is exactly why the cycling keyword fit awkward, situational effects so well in its early years: it let designers print a narrow threat without printing a brick. Read whole, this is a control deck's speed bump, an enchantment that demands the opponent move first and then either bites back or quietly digs toward something better.