| Name | Attribute | Level | Type |
|---|---|---|---|
| Outpost Oak's Elven Soldier | - | 1 | General |
| Outpost Human Soldier | - | 1 | General |
| Outer Box 9 | - | 1 | Interactive |
| Outer Box 8 | - | 1 | Interactive |
| Outer Box 7 | - | 1 | Interactive |
| Outer Box 6 | - | 1 | Interactive |
| Outer Box 5 | - | 1 | Interactive |
| Outer Box 4 | - | 1 | Interactive |
| Outer Box 3 | - | 1 | Interactive |
| Outer Box 2 | - | 1 | Interactive |
| Outer Box 12 | - | 1 | Interactive |
| Outer Box 11 | - | 1 | Interactive |
| Outer Box 10 | - | 1 | Interactive |
| Outer Box 1 | - | 1 | Interactive |
| Out of control mercenary | 58 | General Monster | |
| Out of control mercenary | 58 | General Monster | |
| Out of control fighter | 58 | General Monster | |
| Out of control fighter | 58 | General Monster | |
| Out of control cavalry | 58 | General Monster | |
| Out of control cavalry | 58 | General Monster | |
| Otherworldly Goblin Grandmaster | 80 | General Monster | |
| Otherworldly Goblin | - | 1 | General |
| Otherworldly Goblin | 83 | General Monster | |
| Otherworldly Eye Demon | - | 1 | General Monster |
| Otherworld Walker Punishment | 65 | World Boss | |
| Otherworld Walker Crime | 65 | World Boss | |
| Otherworld Judge Frasho | 72 | Boss Monster | |
| Ossifighter Boney Prince Charlie | 56 | Elite Monster | |
| Osprae | - | 17 | Elite Monster |
| Osprae | - | 23 | Elite Monster |
| Osprae | - | 30 | Elite Monster |
| Osprae | - | 72 | Elite Monster |
| Osprae | - | 15 | Elite Monster |
| Osprae | - | 13 | Elite Monster |
| Osprae | - | 36 | Elite Monster |
| Osprae | - | 73 | Elite Monster |
| Osprae | - | 5 | Elite Monster |
| Osprae | - | 20 | Elite Monster |
| Osprae | - | 35 | Elite Monster |
| Osprae | - | 42 | Elite Monster |
| Osprae | - | 43 | Elite Monster |
| Osprae | - | 49 | Elite Monster |
| Osprae | - | 46 | Elite Monster |
| Osprae | - | 47 | Elite Monster |
| Osprae | - | 74 | Elite Monster |
| Osprae | - | 2 | Elite Monster |
| Osprae | - | 6 | Elite Monster |
| Osprae | - | 48 | Elite Monster |
| Osprae | - | 60 | Elite Monster |
| Osprae | - | 82 | Elite Monster |