Round 29. We lost a player at the beginning of Round 27, and then my 2 teamates went down at the start of 27, I was stuck running around killing zombies all the way to round 29 where I got ambushed by 4 dogs, lol. (Once the other 2 teamates died, they couldn't get weapons in time to be able to help.)
PS: I had over 1200 Kills, which made me 1900 in the world even with glitchers and modders ahead of me