Yalahar dragons (serpent spawn at 1 part, hydra in the other part).
Magician Quarter Cults (2 serpent spawn at last floor with enlightened of the cult)
Feyrist (day and night transition changes completely the difficult of the mobs).
Middle Spike (Several crystal crushers scattered through the place which are considerably stronger than the average mob in there)
Gray island (both deeplings and hive are places that suddenly change from easy mobs to deathly enemies).
Asura Mirror (Facing lvl 150~ asuras till you a mob that does thrice the damage called "true asura")
MOTA (fury is the weakest mob in there by far, but is also the majority of the respawn, you could find hellhound, floating savants and demons).
Mino Cults (Mino zealot is the only thing that turn a lvl 50 hunt into a lvl 200 one).
Oramond Raids (surface west area, and all wildlife raid, beside they don't change the creature type, they add new ones in greater numbers)
Lower Roshamuul (beside you need a whole ss to trigger it, the sight of surrender apparition ruins the hunting ground for lower levels).
Anniversary Raid (deadly mobs appear in multiple low lvl areas, it just happen every 5 years tho).
Tarantula-Gs Cave (You find a hidden group of giant spiders in a floor of tarantulas)
Bounac Surface (it's a decent place to hunt deers, but if you happen to go near the crypt at night you will find crypt wardens which are extremely dangerous compared to a deer).