Earlier quoted context omitted.
Early on, creatures learned skills just like players did. In the alpha, this led to wolves who hunted bunnies, and some bunnies the bunnies escaped and learned a little, and eventually there were both dire wolves (their name actually changed to "wise elder wolf" or something) and vorpal bunnies. These latter ones killed many unsuspecting players in the alpha, and we had to remove the creature learning because it was…
I remember the vorpal bunnies. I seem to remember a bug where they would sometimes appear as an energy vortex sprite... Can you elaborate on why the creature learning was bad UX? Did people get irritated when the wolves were killing their rabbits?
The energy vortex sprite was a different Easter Egg iirc. And sometimes, you could get energy vortices that were llama-shaped...