Note: These are selected based on the fact that they have many rooms with more than 4 mobs. We are going to level in those rooms so we can take full advantage of aoe attacks. Explore the areas a bit to get a feel of where the rooms are. The indicated level range is not absolute as it changes with your character power so feel free to stay longer/less in an area.

hatch 1-25
grotto 25-50 (Progress roughly in this order: Red lava, Labyrinth, Ravine and Amethyst sea)
oz/hedge 50-70 (You would alternate between the two but always clear oz first (the ants and the clouds) so it can repop while you level in hedge (enter hedge in room 15154 for higher level mobs))
darklight 70-80 (level in the starting area up until the gates; be careful with the some strong mobs mixed among the weak ones avoid them if you can since they can bring down the efficiency)
ft1 80-100 (Kill the dwarves in room 1214 when you are able to since they repop together,  same for room 1224; generally stick with bluebirds and robins until you can kill the fishermen. Kill the goose only if you can tank them)
ftii 100-120 (pretty clear progression, many  “sections” has a room with 4+ mobs only spend time in these)
nanj/ddoom 120-135 (same logic with oz/hedge: for nanj kill the good mobs in entrance and the hands in room 11251, you might want to push the possessed rock south if you can so it’s easier. In ddoom hunt sunrise to reach the area then same logic with ft1, kill the mobs in room 4216 and the guards that guard the room before it)
arisian 135-145 (pretty self-explanatory once you explore the map, don’t need to go into the maze)
adal 145-160 (same as above)
origin 155-170 (enter cold and voila!)
tol 160-186 (very clear how it goes)

186-200 ask for a drag 🙂