At the very same time that Teron Gorefiend and his warriors finished conquering the outside region of Zangarmarsh, Mephistroth and Kargath have finally arrived at the gates of the dungeon fortress. Leading an elite group of demonic warriors, the forces of the Legion fiercely storm the gates down, and made their way inside. Aware of the unseen dangers around the shadowed dungeons, the forces of the Legion ready themselves for an ambush. Kargath instantly becomes enraged on seeing once more the dungeon cells where he and his brethren used to be imprisoned by Illidan and his forces.

Kargath: "Damned these cursed dungeons! I will never forget of how Illidan locked us within these cages, and made us prisoners in our own lands! Damn! I'll make sure that I would get my revenge!"

Mephistroth: "Let us find that Shadowkeys in this dungeon quickly. It is crucial that we claim it."

Knowing that the draenei wardens lurk around every corner within the dungeons, Mephistroth and Kargath made it sure to assemble the best demon warriors they have, which consist of bloodfiends, hellhounds, eredar diabolists and voidwalkers. The forces of the Legion search every corner within the prison dungeons, fighting against various groups of draenei warriors, consisting of vindicators, stalkers, harbingers, and seers, which they encounter on different areas of the dungeon on both the former cell divisions for the demons and the fel orcs. Fighting every group of draenei warriors they encounter, Mephistroth and Kargath lead their warriors towards the innermost area of the dungeon.

Kargath: "These draenei mongrels are pathetic! I'll make sure they pay dearly for locking us here!"

Eventually reaching the deepest area of the dungeon, the forces of the Legion come across the last group of draenei that stands at the gate outside of the innermost chamber. Amongst the last group of the draenei warriors is none other than the Elder Sage Akama himself. The warriors of Akama are composed of vindicators and seers. Upon finally meeting one another, the two opposing groups ready themselves for a battle. Mephistroth and Kargath set forth, and begin to speak with Akama.

Akama: "Bladefist! So you return in these halls again, and I see you had brought a new friend here with you! Tell me something, you savage beasts! Did you missed being imprisoned in your cages?"

Kargath: "Akama! I will chop your tongue out, draenei! I will make sure that we get our vengeance upon all of you for locking us in here! You will suffer dearly before I give you your painful death!"

Mephistroth: "We came here for the Shadowkeys, Akama. You would do well to surrender it now."

Akama: "And who are you supposed to be, dreadlord? Another pathetic demon of the Legion?"

Mephistroth: "Be careful who you speak with, draenei! I could easily kill you and your lackeys if I want to right away! I am Mephistroth! I am one among the others sent by Lord Kil'jaeden in here to destroy all of you, and reclaim Outland for the Legion! You and you master, Illidan, are soon to fall, Akama. You may as well give us the Shadowkeys to the Black Citadel! Don't waste our time!"

Akama: "You will have to defeat us for it, demon! I would like to see you all try and take it then!"

Kargath: "As ever, you draenei are a bunch of stubborn bastards! We should have finished you all down to your extinction long ago! No matter, we will take those damned keys one way or another!"

Right then, the forces of the Legion clash against Akama and his draenei warriors on a fierce battle. Akama and his group are showing up a great fight as they pour out all their best upon their abilities. However, the combined strength and power of Mephistroth and Kargath give them the upper hand. The group of draenei are able to take down many of the demon warriors in the battle, but the forces of the Legion eventually claim the victory. All of the draenei warriors have been killed, except for Akama himself. Though still alive, the draenei Elder Sage is now lying battered and injured on the floor as Mephistroth and Kargath approaches him, and begin to ask for the Shadowkeys once more.

Mephistroth: "It is over, old draenei. You are defeated. Hand me the Shadowkeys now, or die!"

Akama: "Foolish demon! If you want the keys, then go get it behind this gate! That is, if you can!"

Kargath: "I had enough of this! I shall rip your guts apart if it means to find that keys, Akama!"

Mephistroth: "Hold, Bladefist! Apparently, he is telling the truth. He doesn't have the Shadowkeys with him. I sense a strange dark power in this chamber. One I feel who has the keys that we seek."

Akama: "I gave him the keys right before all of you came! Let us see if you can defeat him for it!"

Kargath: "Alright, let us barge inside and kill whoever is in there, then claim those damned keys!"

Mephistroth: "No. I must ask you to leave this one to me alone, Bladefist. I would suggest that you stay out here and… take care of our old draenei friend. I sense a great power from this being within this gate, a power derived from the fire and shadow of the Legion. I am surely up to challenge it!"

Kargath: "Very well, dreadlord. Do as you may please, and win those keys. As for me, as much as I love to tear the heart out of this old mongrel, perhaps I shall let him have a taste of the dark bitter imprisonment in these cages as he did to me and my brethren! Yes, that will only be fitting indeed!"

Mephistroth enters the gates of the innermost chamber of the dungeons. Once inside, the dreadlord discovers the being with great dark powers that he had been sensing. Within the chamber stands a night elven demon hunter. The name of the night elf demon hunter is Theras, and he is another one of the four elite lieutenant warriors of Illidan. Upon confronting each other, Mephistroth discovers that Theras has indeed the Shadowkeys for the throne chamber of the Black Citadel. The dreadlord then begins to speak with the demon hunter as they ready themselves for a fight against each other.

Theras: "I am Theras, a proud warrior of Lord Illidan! I know why you have come dreadlord! You shall never take the Shadowkeys, demon! You will have to defeat me first if you want to claim it!"

Mephistroth: "You no longer need to tell me what I must do, night elf! I shall gladly claim the keys by killing you! Let us see if you could match your strength and powers against me, demon hunter!"

Theras: "My master destroyed the greatest of your kind, your very own brother! Now, I shall claim the glory of defeating you myself! Then, I shall also put an end to the rest of your lapdogs outside!"

Theras and Mephistroth begins to clash against one another upon a vicious one-on-one battle, with the demon hunter striking with his warblades, and the dreadlord assaulting by his deadly claws. In terms of physical combat, both of them prove to be strong and deadly fighters. Right then, the two began to focus their magical energies, and cast their harmful spells against one another in a vicious contest of powers. Mephistroth casts a powerful spell of Carrion Swarm on Theras, blasting off a harmful shadowy wave of magical swarms of bats and insects. In retaliation, Theras sends back a bolt of Mana Burn spell on Mephistroth. The demon hunter also engulfs himself in flames with his Immolation spell. The two of them would continue fiercely fighting against one another for a time.

Like Illidan and all of other demon hunters, Theras has the ability of Metamorphosis, transforming themselves into powerful demons. Theras uses his Metamorphosis spell in their one-on-one battle. Impressed by the powers of the night elven demon hunter, Mephistroth uses his own most powerful spell as he magically summons one infernal demon from the nether. Falling out from the skies and breaking through as an ethereal fiery rock, the infernal rises from the ground as a strong minion to be commanded by the dreadlord. Theras, in his demon form, is now fighting both Mephistroth and the summoned infernal. Despite putting up a good fight, Theras is not as powerful as Illidan himself and is overwhelmed by Mephistroth and his infernal minion. The dreadlord eventually defeats and kills the demon hunter. Standing victorious, Mephistroth takes the Shadowkeys from the corpse of Theras. Using a dark fire spell, the dreadlord burns out the remains of the demon hunter into ashes.

Mephistroth: "Finally, the Shadowkeys is ours! Once we invade in the Black Citadel, we will have the easy access to the throne chamber. We are now one step closer to our victory here on Outland."