[Gameplay] Kalista Spear Stacking

Occasionally when farming as Kalista, the auto attack will connect and activate rend instantly after with out consuming the cooldown or leaving a spear. The animation happens as the auto was followed by rend, the only problem is the E-Key was not pressed. As far as conditions for the bug, it only seemed to happen on minions, I did not notice the interaction with champions if there was one, but it is random so it could very well still affect champions. I noticed this bug happened in all of my last 5 games on Kalista.