I got with a good team pretty early, and we grouped up and just... the enemies of Talon were eliminated. Thoroughly.
I carded or got play of the game every. single. game., including as Widowmaker. I came this close >< to four-golding as her on defence at Horizon, and still had three golds and carded for it. I also carded as her in Volskaya, for kill streak. (11. No deaths. No objective kills or time, either, because the enemy never set foot on the objective. Their Pharah got close, once. I stopped her, and she started hiding from me. They were terrible.)
The game at Horizon, though - hoooooooo. I had a one on one with a Genji who really, really, really should not have lost a solo melee fight with Widowmaker in close quarters, but wow he sure did.
I was holding the point solo when he charged in with his primary attack - and, conveniently, hit my mine. Then it was just machine gun (and another mine, I had one ready) vs. shuriken and I took him apart. Three of my team rushed back to help just as I killed him, and they came up the stairs to see me standing over his body. Mercy threw heals at me as they just stopped for a moment, all, "...oh. We thought you might've needed help."
I didn't hit my laugh emit, but I certainly should've.
It wasn't just Widowmaker, though. Mercy (before we teamed up, a smaller version of the group with more weak links, I made them competitive), Pharah (which is when we had some weak links replaced and formed a team), Tracer, Widowmaker, D.va - I was just in charge in all incarnations. By the time I hit Widowmaker, it was like the assumption was that I was going to be fine. Then I proved that correct.
I can make a weak team competitive. But when I'm really on my game... I can make a good team an unstoppable force.