In the easy/medium exterior section on Nukara, sometimes the Tholian ensigns kind of rear up and spread their arms out, and a sort of energy burst starts to form around them (not the usual shooting). I have played this mission a lot and only seen it a few times. I always blast them before what ever it is completes. And in the interior easy/medium mission, sometimes the Tholian Lieutenants kind of freak out and then explode into a million pieces. I can't make it happen regularly. What's up with these two things?