Reins of the Vinesteed
Most creature-pumping Auras carry a built-in tax: invest mana, and a single removal spell on the host turns the whole investment into a two-for-one against you. This one answers that tax with a typal hook. The +2/+2 is incidental; what justifies the four-mana cost is the recursion clause underneath it. When the enchanted creature dies, the Aura can claw its way back out of the graveyard and reattach, but only to something sharing a creature type with what just died. The design idea is that in a board full of, say, Goblins or Elves, the Aura is not really attached to one creature so much as to the tribe itself, surviving as long as the type does. That makes it less an Aura than a recurring buff that hops down the line, each death moving it to the next legal host. The friction is honest: outside a dense single-type board the return clause whiffs, so the card is dead weight in a midrange shell and an engine in a focused one. It sits with a handful of typal Auras that try to fix the card-disadvantage problem at the source, by refusing to die when its host does, and it commits hard to that single solution rather than hedging with a cantrip or a smaller, safer bonus.
