Kitsune Riftwalker

Protection that points inward at the same block it shipped with. Most protection keywords name a color or artifacts, broad categories that turn up across every set; this one keys off Spirits and from Arcane, two tribal axes that mean nothing except against a specific kind of opponent. That narrowness is the entire pitch. A 2/1 for three is otherwise a body you forget exists, but against a deck built on Spirit creatures and Arcane spells it becomes a clean attacker their Spirits cannot block, an untargetable threat that ducks half their removal and aura toolbox, and a safe blocker that survives any Spirit it stops. Note the limit: the protection only works while the Fox is on the battlefield, so it does nothing to keep the creature spell from being countered on the stack; it earns its keep once it has resolved and is in play. The design does almost nothing in a vacuum and quietly dominates against the right kind of deck, which is the trade you make when you tie protection to creature types and a spell subtype rather than to color. It reads as a piece of narrow hate that hedges a small evasive Wizard against Spirits and Arcane instead of stapling on a punishing trigger. The result is a card whose value swings harder on what sits across the table than almost anything in its mana range.