Originally Posted by
Ethenil
Okay, here we go!
A mak'gora is a ritualistic duel to the death, in which each person must choose one and only one weapon.
In Nagrand, after the Alliance and the Horde were fighting a lot against the Iron Horde, Thrall steps in and declares mak'gora against Garrosh Hellscream.
Garrosh chooses Gorehowl, and Thrall the Doomhammer. I suggest you watch the Nagrand finale cinematic to see how it plays out. In the end, Thrall commands the elements to kill Garrosh, effectively cheating in the rules of mak'gora.
For having cheated and abused of the elements, they become silent to him, presumably for a time until he "learns his lesson".
Thus, after Thrall loses the Doomhammer to some demons and it falls into the Deepholm, and the player shaman helps retrieve it, Thrall decides to pass on the weapon to the shaman.
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As for Archimonde being summoned, Gul'dan used the Cipher of Damnation and considerable time to manage to open the Black Gate to Archimonde. In the Main Universe, Gul'dan had used the same Cipher to raise the Hand of Gul'dan in Shadowmoon Valley and sever the connection between the orcs and the elements.
In AU Draenor, the combined armies of the draenei and the remnants of the Iron Horde led by the Frostwolf, as well as the commanders of the Alliance and the Horde, are only victorious against Archimonde thanks to the three legendary rings crafted by Khadgar and the players. These rings channeled and combined the elemental fury of Draenor, the arcane might of the Gorian Empire, and the holy blessing of the naaru.