River Kelpie

The clever trick here is that the body is its own first trigger. Persist returns it from the graveyard when it dies, and "whenever this creature or another permanent enters from a graveyard" reads its own arrival, so the first death cantrips as it crawls back. From there the design is a card-draw engine bolted onto two of blue's least-explored value axes at once: recursion-as-entry and graveyard-as-launchpad. Most blue draw payoffs of its era cared about spells cast from hand or creatures cast normally; this one rewards the opposite, paying out whenever a permanent crawls back from the yard or a spell is cast from it. That makes it a magnet for unearth, flashback, disturb, and any reanimation effect, including effects controlled by your opponents, since both triggers read the table rather than the owner. It is a payoff in search of a graveyard deck, the kind of build-around that does nothing in a vacuum and snowballs the moment the graveyard becomes a second hand. The persist counter is the natural ceiling: it can only die-and-return once on its own before the -1/-1 counter disqualifies the second loop, so the engine wants to strip that counter to keep the recursion lever live. A +1/+1 counter cancels it the instant both counters meet, and dedicated counter-removal does the same. Built right, the density of draw it stacks onto a graveyard theme is rare for blue; built wrong, it is a 3/3 that comes back smaller.