Deers and Stags easy to trick to come back
When running after deers and stags you never manage to catch up, but if you run back some after they have run out of visible range they will start running back towards their starting point again and you will be able to hit them as they will run right onto you when heading back.
Seems like they should be getting scared of you and run away again if you are within range also on that return run.
That's more of a leash mechanic/design mechanic than a bug I think...but we'll see!
This also applies to rabbits and foxes but those you can usually outrun anyway