Journeying into the depths of Stonetalon Peak, the Horde forces came to a cross roads. Thrall suggested they split up to find the end of both passages. Thrall and a party of Orcs and Trolls took the right path, while Cairne and his Tauren warriors took the left. Cairne warned Thrall to be careful, since all manner of creatures dwelled within the mountain's depths.
The Orcs journeyed through the winding tunnels of the mountain, coming under attack from undead, quilboars, kobolds and other monsters, as well as parties of humans, dwarfs and elves ordered by Jaina to delay their advance. Eventually, they came to a sealed chamber containing a statue of a Night Elf princess. The statue communed with Thrall, identifying itself as Aszune, and that none could pass until her 'heart' was returned to her. Returning into the tunnels, the Orcs came upon a band of harpies attacking a red dragon. The Orcs waited until the harpies had killed the dragon, then fell upon the harpies, killing them all and recovering from the dragon's hoard the gem known as the 'Heart of Aszune'. Thrall returned the gem to the statue of Aszune, freeing her spirit and opening the way to the chamber beyond; the lair of the Oracle. However, there was no way to cross; Thrall reasoned a spectral bridge was present, but there was no way to access it. Thrall hoped Cairne might find a way to activate it...
Cairne and his tauren kin meanwhile proceeded down their path, encountering similar resistance from the denizens of the mountains. At a junction in the tunnels, they came to an outcrop overlooking a pit full of Quillboars; too many for the Tauren to defeat. However, Cairne noticed the pit was in fact a spiked trap, and triggered the device, killing all the quillboars in the pit. Sifting through the bodies, Cairne recovered a strange gem which he recognised as the spirit stone required to activate the spectral bridge to reach the Oracle. Proceeding through the caverns, Cairne and his men rejoined with Thrall in the chamber and activated the bridge, crossing into the Oracle's chamber...
Jaina and her forces were already present; upon seeing the Orcs had caught up to them, Jaina and her forces prepared to fight to the death, but a stern voice rang out, demanding that there would be no violence in the place. Thrall recognised the voice; they were not speaking to an oracle, but the Prophet. The Prophet confirmed this, and stated he had brought them to the place for a purpose. The Prophet explained that the Burning Legion had returned; having already annihalated Lordaeron, Kalimdor would be next to feel their wrath. Only by uniting would the humans and Orcs be able to resist the oncoming shadow.
Jaina dismissed such an idea as madness, but the Prophet impressed upon her the severity of the threat posed by the demons. He told Thrall that the demons had already corrupted Grom Hellscream and that if they didn't act soon, he and the entire Orc race would be lost to the demons forever. Thrall refused to let this happen, insisting he would die before he let such a thing occur. The Prophet explained that Hellscream was key to the destiny he had promised the Orcs, but that Thrall would need help to free Grom. Jaina tried to back out, but the Prophet was adamant; for the sake of all Azeroth, the Alliance and the Horde must ally together.