What was that 'Beginner's luck' moment you remember?

I saw a team trying to fight their way into the overhanging shanty building at bridges on KC during pre-season 1. They were at the top of the slope in the north and my squad was approaching from the south-east at a much lower elevation, not yet in the fight. So just as I saw that my team was about to charge into the chaos I threw a hopelessly long ranged frag grenade into the structure where this third team apparently was. My expectation was to cause a little inconvenience while I closed the gap but instead it was an instant triple kill.

Literally my teams first contribution to the battle. At no point did I see the people I killed in their living state. All I had to go off was some stray bullet trails that they had sent toward the other aggressing squad.