Rokhan and Rexxar found humans on the coast of Durotar after they got to the observatory in Gar'thok's Outpost, and when they reported to Thrall, he sent them back to find the outpost ruined, and the humans quite hostile.
Rokhan began to worry about his own people on the Echo Isles, and thought that perhaps they should come to the mainland to avoid any danger. Thrall agreed, and sent Rokhan and his band to the Echo Isles to warn Vol'jin and see them off the island.
After destroying the battleships that blocked their path and lighting signal fires for the outlying village, Rokhan and Rexxar were sent to a summit in Thrall's place. When they were ambushed, Thrall, hoping to finish things peacefully, sent Rokhan and his friends to Theramore Island to secretly parlay with Jaina Proudmoore.
With Jaina's aid, they discovered the invaders were led by Jaina's own father Admiral Daelin Proudmoore, who was determined to wipe out the Horde in Durotar. Rokhan battled alongside Rexxar as they hastily traveled around the Barrens enlisting aid from their allies. Finally, the human and orc forces clashed in a titanic battle at Tidefury Cove, and when the orcs emerged victorious, they chased the humans back to Theramore. Rokhan helped to lead the raid on Theramore, and battled Daelin Proudmoore's elite forces beside Rexxar. After Proudmoore's defeat and the end of the war, Rokhan was honored by his people and Thrall's.
Afterwards
This section concerns content exclusive to the Warcraft novels or short stories.
Tensions remained high between the orcs of durotar and the humans of Theramoore. War nearly broke out once again, due to the scheming of a minor demon Zmodlor and a few Burning Blade cultists. Rokhan was still in Thrall's service as a scout - his finest - and made a sudden appearance to warn the Warchief of reinforcements to Northwatch Hold on the border between human and orc territory. He is described as having a surprisingly gentle face for a troll, with kind eyes.CoH #?
Rokhan was rumored to, and still may have been sent on an important mission by Vol'jin.HPG 179