The tabletop gaming club at my uni had a Tomb of Horrors competition, which I just got back from. A bunch of different teams were all racing to see who could get the farthest in the recently released 5e version of the Tomb. I went with a couple of friends, and we got placed with three other randoms, but that mostly worked out. I played a cleric, where my job was primarily to stand behind the rogue, applying Guidance, and performing the Help action as they searched for traps and secret doors. We moved very, very, very slowly through the dungeon, and spent about 45 minutes before we even went 15 feet into the dungeon proper, after almost dying to a false entrance. We found a secret door early on, which led to Dart Hell, which took us about an hour to get through. Somehow, all six of us managed to survive that, with the rogue only dying for a second, before the DM realized that spikes do not insta-kill. We started to pick up the pace, as we got a better sense of how the dungeon was designed, and how to watch out for death traps, speeding through the orb room, avoiding the gear stealing teleportation door many other groups fell into, practically ignoring the chapel (except for the fact that our barbarian did walk into the gender/alignment changing mist), and only TPKing in a pit of lava. We were down to our last hour by that point, so we were moving really fast, and weren't being as thorough as we should have been. We only had two combat encounters, and, as tenth level characters, we managed to absolutely shit on both of them, which was a lot of fun, but the traps were the real 'killers'. IIRC, our fighter took about 100+ damage from traps alone, especially darts..
All in all, we didn't win, but we did tie for second when it came to distance, but we got penalized for TPKing, which left us in a solid third place, only a few rooms behind the group in first.