a bowling ball, or just bowling in general.
I and compatriots mingle about
Here at the end of a long round-a-bout.
You are, perhaps, a bowler and the rest of your team, at one end of the lane.
More likely, you are a bowling ball, waiting with other balls in the ball return.
The round-a-bout perhaps references the ball return system.
The enemy assembles itself straight and tall
in close-knit formation—a flying-wedge wall.
The pins, aligned in wedge-shaped formation on the other end.
We attack one by one with the will of the masses!
With skill and with speed, knock them right on their asses!
Bowling balls are hurled by the players, one by one,
with skill and speed to hit the pins that are standing and to knock them down.
But more! They are coming, matters not how they've fared.
Even if none of their brethren were spared.
Even after a strike—or a spare—the next frame resets all the pins.
Thanksgiving day Massacre:
In bowling, three strikes in a row is a "turkey".