I'd noticed in Annabots that I seemed to be getting some double-kills with single shots, and poking around, I'm under the impression that domino shots are actually a thing in-game.
I think I got one yesterday. Temple of Anubus, on offence, second point, I'm hanging out on my favourite perch, shooting onto the point, really kind of waiting for my team to get back out there as we'd captured part of the point but then got stomped.
I see some movement on the point, and I fire one shot in - Double kill.
I think maybe I got my first domino shot in quickplay.