Takklemaggot

A disease aura built as a self-perpetuating curse, and one of the strangest pieces of state-tracking the early game ever asked players to maintain. The -0/-1 counters tick the host down on its own controller's upkeep, which already inverts the usual aura math (your opponent is doing the work of killing their creature for you). The real design swing is the death trigger: the plague jumps. The choice belongs to the dying creature's controller, but the legal targets are any creature this card could enchant, which means the obvious play is to hop the parasite onto one of your creatures and turn your own removal back against you. If no legal creature exists, the aura reattaches to nothing and converts into a passive damage clock on the player directly, shedding its enchant-creature clause to do it. That last mode is the part veteran rules students remember, because it required the card to survive on the battlefield as a non-Aura enchantment, a state the rules of the era handled only awkwardly and which has been re-templated more than once across reprintings and oracle updates to keep it functional. The flavor reading is exact (a parasite hops bodies until there are none left, then infests the host directly), and the mechanical reading is a designer working out, in 1994, how an aura could survive its enchanted creature's death. Most of the answers Magic eventually settled on, totem armor, bestow, the curse subtype, came decades later. This card asked the question first, long before the vocabulary existed to answer it cleanly.