When you reach level 23 you will want to start heading southeast away from Morheim. Down the path where you had to kill the Brax you will find Medea. She is where I am standing on the map.
She will give you a quest called "Outfighting Arachnas". This quest requires you to kill 12 Shade Arachnas. You probably seen this while running down the path, they can be found just west of Medea. After you kill all 12 of them return to Medea and turn in your quest. Continue down the path to Patamor Thicket.
Here you will find 3 trents with quests for you. Accept all of the quests that they have. You should have the following quests:
Now around Patamor Thicket you will find Mushrooms, some small some big. You will need to kill 25 of the small ones, the Tumbling Fungie and 15 of the big ones, Bluenet Fungen. Once you kill all of the Fungi like creatures return to Keindor and turn in your quest. Now that you have that done you will want to head up the hill to the east and speak to Kistig.
Turn in your quest to Kistig and accept the new quests that he has. Now what you will want to do is head north and kill the Grove Arachna's for 5 Arachna Poisons. You will also want to kill 3 Rock Spirits and 8 Mud Spirits. Once you've completed these two quests return to Kistig and turn them in. Accept the follow up quest from Kistig and head back north. Now you will want to collect Research Materials and a Potion Bottle.
The Research Materials can be found in the old barrel and the potion bottle can be found in the wooden box. The old barrel can be found where I am on the map and the Wooden Box can be found where the X is on my map, both in the picture below.
When you get both materials return to Kistig and turn in your quest. Accept his new quest, which next time you're in Pandaemonium you can turn it in (If you remember of course). Now from where you are, you will want to head a bit west, to the Sprigg Habitat.
Here you will want to kill the Spriggan Gatherers and Wardens until you get the Elim Essence. Once you have that return to the Trents at Patamor Thicket and update your quest. Now, continue west to our little camp right outside of Musphel Gate.
NOTE: While killing the Spriggs for the Elim Essence you should also collect Rabano if you're able to gather it. It is used for a quest coming up.
There are a few quests available to you from this camp, but not many of them are worth doing. If you've been raising your Gathering Skill while leveling, I recommend doing the quests that require you to turn in 15 Twisp Fiber and 15 Vinna. If you can't gather them, buy them next time you're in town and turn them in next time you're here.
Now, from town you will want to head west to Lif. Lif is a fisherman who is standing on the dock over looking the lake.
Turn in your Gadil Gathering quest to Lif and accept the other quests that she has. After you've done that head north of her to Vivi, the Sprigg whom you have to turn a quest into. Turn in your quest to Vivi and accept the new one she has to collect 10 Rabano. If you where able to collect the Rabano from earlier, turn in this quest. If not, return to Lif and turn in your quest.
What you will want to do now is kill 9 Blue Monitors that surround the lake. After you kill all 9 of the Blue Monitors you will want to return to Lif and turn in your quest and accept the follow up. You will now need to go into the lake below Lif and kill creatures for specific items. You will need to kill the following creatures for the following items.
After you get all of the ingredients required return to Lif and turn in your quest. The other quest she has, "Good Tools After Bad" just isn't worth doing, so skip it. From Lif continue along the road west to the "X" on my map.
Here you will find the Hill of Belemu. You will need to use your Essence of the Elim here to complete your Campaign quest "Petrifying Elim". The Essence of Elim is the little grape shaped thing in your inventory and a picture of it can be seen in the earlier sentence of this paragraph. Use it, watch the cut scene then return to Nabaru at Patamor Thicket. Turn in your quest and accept the new one he has to be turned in at Kellen's Cabin. Return to Kellen's Cabin and turn in your quest.
You now have two options, head over to Brusthonin and continue questing here (Not recommended) or Grind out two levels (Recommended). The best places to grind for you atm are the Fungen/Spriggs until level 24 then at the entrance to mount Musphel till 25.
The decision is left up to you. Once you reach level 25 you will be given a campaign quest to gain access to The Abyss. The next part of my leveling guide will fully cover this quest.