Most hated villains? too long a list to make but ill settle for Ruin Mages. At their level they hit like a truck and have a combination of offense and defense that is nearly team breaking.
Most hated group. VAHZILOK VAZZZZZZZ!! dear god any one group that makes me actually shudder in anger its vaz the amount of damage they do at their level range is staggering and worse they have tox damage which is one of the least defended against.
Most hated map? that thrice damned and be damned again Lab Map, most specifically the room with the Lab machines. I HATE with a capital H A T E that room. it is just a mess with too many corners to hide a mob in and the possibility rng to get simultaneously hosed and rewarded at the same time. one time back live when we gleefully blew up the lab equipment to see what we got, my team got 4 FOUR!! end debuffs. we spent nearly 5 mintues with no end felt like we were fighting malta sappers
oh and did I mention we were on a synapse TF at the time so we were against clockwork on top of it all.