Path of the Orc Raider
1) This quest starts in The King's Hall in Orc Village with Prefect Karukia. She tells you to hunt Goblin Tomb Raider Leaders, which will cause the Kuruka Ratman Leaders to show up, then kill those as well.
2) The Goblins Tomb Raider Leaders are found near the Immortal Plateau Northern Region.
As you kill them, randomly the Ratman Leader will show up. The Ratman Leader showed up for me anywhere from 3 Green Blood quest items, and 10 items. You have to do this until you have 10 Kuruka Ratman Teeth so it takes a while to do. The drop rate is 100% though.
3) When you have 10 go back to Karukia and she asks if you want to go to Gludin or Schuttgart. I chose Gludin. She needs the heads of the Umbar Orcs.
4) The Umbar Orcs are on the East side of the mountains, even though the pushpin looks like it's on the west, so it's best to port to the Spider Nest or Necropolis of Devotion and run over. You only need 2 items and there are plenty of the quest mobs, so it should only take 5 kills or so.
5) Then go to Gludin to the Orc Guild and talk to Prefect Kasman and earn 81,900 adena, Mark of Raider, 295,862 exp and 17,354 sp. This is as of CT2, in previous versions you do not get the adena and the exp/sp is much less.
6) Then if you are level 20 talk to High Prefect Osborn who is next to Kasman and change to Orc Raider. You will also receive 15 Shadow Item Exchange Coupon D Grade.