Unsettled Mariner

A soft tax on interaction, wrapped in a body that answers to every tribal lord in the game. The changeling line makes the 2/2 a legal member of any creature-type deck, which is the mechanical reason it can slot into decks built around Merfolk, Spirits, or Humans without diluting the count; but the real work is the second ability, which levies a one-mana tax on any opponent spell or ability that targets you or your permanents. That is a Mausoleum Wanderer effect stretched across your whole board and yourself: removal, edict-style targeting, burn to the face, forced discard, all of it now costs an extra mana or gets countered outright. The design cleverness is that the tax reads narrow (it only fires on targeted effects) but covers a huge share of what an opponent actually wants to do to a creature deck. Its natural ceiling is the effect it cannot see: sweepers and symmetric spells walk right past it, so a Damnation or a Toxic Deluge answers the whole board without paying a cent. What it protects against is the point-and-click interaction that aggressive tribal decks fear most: the cheap kill spell on your best threat, the spot removal on your combo piece. As a two-drop that both counts as any tribe and makes an opponent's targeted answers worse, it is a rare piece of protection priced to fit the curves it defends.