Artifact - 3
Whenever one or more creature cards leave your graveyard, create a 1/1 black Bat creature token with flying.
This seems like it has Dredge or Survival potential, and can even be maindecked by either with not much retooling of the mana. It majorly protects against graveyard exile effects (too late with your Rest in Peace? death by bats.), but even proactively works with the dredge mechanic itself as cards move to hand or to play. Nice synergy with old Squee, if that's a thing. It's a new avenue of attack for grindy games.