After killing 15 demonic trees, Mordrick Maensel of Raven's Dust Castle will ask you to kill Ghundarg Garak, who is in the Orc city. Go back to him and he will ask you to translate the Orcas.
Go see Morindin Tennglaw, NPC hunting above Tarantula Lake, tell him to translate (requires 5,000 gold).
Report the translation to Mordrick Maensel.
Gain: