Self Defense Video Analysis.  Your input appreciated even if you don't know tactics, just give us your thoughts.

This one is situational awareness and the unexpected.  Masked man throws a grenade inside of a nightclub in Ukraine. 

What went wrong?
What shouldve been done?
Would it have been legit to shoot?
Situational awareness?
Would you have known it was a grenade?


 Same thing could occur here with a pipebomb.

https://www.liveleak.com/view?t=ChIcG_1528629261

Hard to say without any audio. Really so little time to react once he threw it.

Amazing no one died though.

Of course not being there "in the moment"  this is all Sunday armchair quarterback stuff.

What went wrong?
The guy on top that saw a masked man in black on the stairway did absolutely nothing until the device was thrown

What should've been done?
Guy mentioned above could have blocked the throw of the device or he or whom I see as the bouncer who seemed to witness the act  could have kicked the device under the rail onto the stairs and into the path of the fleeing terrorist (aka Karma)

Would it have been legit to shoot?
Before or after ?

Situational awareness?
The guy on top that saw the masked man was totally aware of "something" going on, just failed to recognize and or react.
Was he running after the bad guy or running away from the bomb ?
Would you have known it was a grenade?