Soulherder

The engine turns on a single word: the end-step ability exiles another creature you control, and the counter trigger fires whenever any creature is exiled from the battlefield. So the blink never points at the Spirit; it aims outward, and each flicker drops a counter on this 1/1 as a byproduct. That split structure is why it demands a board rather than sitting in a deck as a value creature you slot in blind. Left alone it grows by one and re-triggers a single enters-the-battlefield effect per turn, which is upkeep, not payoff. Aim it at real ETB text (a card-drawer, a bouncer, a token-maker) and the end step becomes a recurring value loop that also compounds the body into a clock. The timing is the constraint that makes it fair: the exile-and-return fires exactly once, as your turn winds down, so it doubles as a way to untap a creature you tapped for attack, sending it back ready to block through your opponent's turn. It is not a held-up trick; you cannot flash it in to save a creature from a removal spell, because the window exists only at that one point in the turn. What it did was codify white-blue flicker as a counter-driven value-aggro shell rather than a pure control deck: a creature that both powers the loop and, if left unanswered, closes the game while the value stacks up behind it.