TF2!
Went on a 13-2 killing spree as a sniper with the huntsman. After then taking another 4 deaths, changed to soldier, because my team had zero defense. Our three engineers are somewhere, I have no idea where, I looked, and couldn't find them.
Things got better. We got their intel in our sewer. We killed all its guards. And then one of our guy's picked it up, and ran it back into the red team base, with half our team screaming at him. Red team of course let him walk right back in, and killed him deep in their base. No votekick available.
At that point, it was basically useless. I went soldier, and racked up another 20 kills and 4 deaths. Of my 10 total deaths, ZERO came from outside our base - I never even left the base. I spent my whole time, 33 kills worth, killing intruders. They came up through the grate, from the sewer, through the front, over the battlements... absolutely everywhere. Zero defense at all.
I distinctly recall watching my rocket fly through an enemy soldier, who returned fire and killed me. I respawned, and as I was starting to move again, the door of my spawn room was opened by my own team, and the same soldier's crit rocket screamed through and killed me. Next respawn dropped me through a hatch on top of a heavy.
So I told the team they were all fucking worthless and left.