Siren's Ruse

Flickering your own creature to dodge removal is old technology, but most blink effects pay for that protection with sorcery speed or a heavier price. Here the work happens at instant speed for two mana: a spell points at your creature, you exile it in response, and the pointed effect fizzles when its only target vanishes. The narrowness of that answer is the whole design. Because the creature returns immediately rather than at the next end step, the timing math changes what it beats: against a board wipe it does almost nothing, since the creature returns to the battlefield while the wipe is still on the stack, then gets swept up when the wipe resolves anyway. It is equally blank against edicts, which make the opponent sacrifice rather than aim. What it does do beyond survival is reset enters-the-battlefield triggers, which is where it stops being purely defensive and starts pulling engine duty. The tribal rider is what turns this from a strict one-for-one into value: rescue a Pirate and the rebuy comes with a card, so the defensive trick replaces itself. That conditional draw is the deckbuilding gate holding the cantrip in check, tying the payoff to a tribal commitment rather than handing cheap protection to any blue deck that wants it. Note that it can legally target a token you control: the token gets exiled and simply fails to return, so pointing it at anything but a real card is a way to remove your own creature from the battlefield, not save it.