I unlocked the Man vs Tank achievement in Left 4 Dead for taking out a tank by myself without any help from teammates, so I’m clearly hardcore. Sure, it was on easy. Sure, the Tank AI glitched and was stuck in one spot. Sure, this meant I was able to shoot it with just a pistol in order to ensure I unlock Akimbo Assassin as well. But I still managed to do it.
Details? Fine. I was playing the Blood Harvest campaign, and we were on top of one of the train carriages under a big stone bridge. The tank spawned in that area, and tried to get on top of the carriage. However, he got wedged under the bridge where he could see us enough that the AI wanted to charge for us instead of find another route, but because of the height of the bridge he couldn’t quite hoist himself up onto the train. This led to me being able to take him out with just a pistol and win at life. I was afraid the bots would jump in to help, but the tank was just out of their aim, so they just stood there and waited for me to do the job. Awesome.