Suggested Farm #1: Leaving from Boreas Seabed into Pongmei Valley presents several large groups of Rot Wallows that can be killed for their tusks. There is a Statue of Dwayna located just outside of Boreas Seabed that can provide helpful Blessings while farming. The map shows the location of 4 groups of Rot Wallows that can be killed quickly, then the run restarted. (If you continue towards Maatu Keep, there are 2-3 more groups of Wallows.) These groups present little challenge to small teams in normal mode. Note: Rot Wallows tend to spam their skills on minions or spirits, ignoring the players.
Spirit Farmers also work well. Spam your spirits just out of range, then use a Longbow or Flatbow to pull the Wallows from their Island Guardian (even solo novices should be able to handle 3-4 wallows). If you choose to take down the Guardian, target it with your wand or staff so that you reach optimal range; if you stay at that distance, you often won't suffer any damage at all.
A standard 600HP Monk or Elementalist with either hero or human Smiter can also farm the groups easily, since Wallows lack enchantment removal and interrupts. However, bring an anti-knockdown skills such as Fleeting Stability or Dwarven Stability because of the automatic Knockdown from Wallow critical hits; fighting groups without this protection can quickly lead to a knockdown chain and death.