Optimistic Scavenger

The whole payload here is a counter engine bolted to the cheapest possible chassis, and the clever part is how its two triggers overlap without stepping on each other. The Eerie half rewards you the moment an enchantment resolves into play; the Room half is a distinct event, firing only when both doors of a Room have been paid for and the thing fully unlocks. A single Room can therefore pay out twice: once on arrival, again when its second half opens. That doubling is the design's quiet ambition, turning a one-mana 1/1 into the accumulation piece of an enchantment-heavy board rather than a body that carries a game itself. Because the counter lands on any target creature, the growth is decoupled from the Scavenger: keep the little engine alive and stack counters onto whatever actually ends the game. Permanence matters too. A +1/+1 counter is fixed and compounds across every trigger, so the value survives the source's death the way a temporary pump or a token would not. What balances it is a sequencing tax that runs backward from most payoffs: the Scavenger has to be down first, before your enchantments and Rooms arrive, or the entering triggers pass it by entirely. It rewards the player who plants a board early and harvests later, growing into an incremental machine that decides long games one counter at a time.