Notes and Rules Information for Beast Within:
  • If the permanent is still a legal target but is not destroyed (perhaps because it regenerated or has indestructible), its controller still gets the Beast token. (2013-07-01)
  • If the target permanent is an illegal target by the time Beast Within tries to resolve, the spell won't resolve. No player creates a Beast token. If the target is legal but not destroyed (most likely because it has indestructible), its controller does create a Beast token. (2021-03-19)