Lurking Skirge

The premise is a wager: spend two mana on an enchantment that does nothing until a creature dies on your opponent's side, and you collect a flying threat for free. The clever part is where the trigger lives. It fires whenever a creature enters an opponent's graveyard from the battlefield, which means it does not care how the creature got there: combat kills it, their own sacrifice outlet kills it, your removal spell kills it. The card rewards attrition without caring who caused it, so a removal-heavy hand turns its own kill spells into a bonus body. The intervening-if clause ("if this permanent is an enchantment") is the quiet load-bearing part. Once it animates into a 3/2 Phyrexian Imp with flying, it stays a creature and stops watching graveyards, so this is a one-time transformation, not a recurring engine. That single-use ceiling is what keeps a two-mana flier honest. It also gives the card an odd resilience for the cost: it is vulnerable to enchantment removal while dormant and to creature removal once awake, never both at the same moment. This is the kind of Phyrexian-flavored permanent the era leaned on, one that asks you to read the game rather than build around it, betting that any board where creatures die is a board where it eventually stands up and starts swinging.