Very good and interesting card. The delay effect by itself is not OP. Although it can change target, it costs quanta every turn and BB delays for 6 turns for 1 quanta.
The main questions looks like the attack creature part. How about make it 0/5 upped, so no way to use rage potion? Blessing gives the damage of EE, but using 2 cards, and 2 quanta types, so no problem. I think the cost could be 2, just because of Fractal.
People complaining about insta-kills... isnt Maxwell Demon + Fire Shield or Plague insta-kill for most creatures? And anyway, the Warden is not immortal, so just kill it.