This is were the real grinding game starts and is were you want to go hunt as soon as you get tier 3. There are three spacious floors were you can hunt. First level is the easiest floor with still very good EXP/SXP, the second floor have a little bit more mobs and as you walk towards the third floor you will see some of the harder mobs and the third floor is the most difficult with mobs that have a lot more HP but are just as much rewarding in SXP. You will also spend a lot of time doing your dailies for "high density energy stone" (HDES) charges. Every mobs have chances to drop X enchant scrolls.You can access this area by talking to the teleportation lady in towns, click "I'd like to have a hunting ground guide"
Lvl 26-35 for UG lvl 1
Lvl 36-40 for UG lvl2
Lvl 41-44 for UG lvl 3
Pros: Awesome place for EXP/SXP, X scrolls as drop.
Cons: No CDK zone