The siege of Bladespire Citadel was a battle between the Frostwolf Orcs and Horde forces led by Durotan and Thrall, and the Bladespire clan of ogres. The orcs, wishing to gain a foothold against the encroaching ogres and Iron Horde, Ga'nar led the charge against them to gain a strategic position to command Frostfire Ridge. After Durotan and Thrall brought up the rear, they freed the slaves of the ogres and killed the ogre lord Gorr'thog in [10-40] Last Steps.
After joining the Iron Horde, the Bladespire ogres came across the wounded Ga'nar and delivered him to the Iron Horde. Sometime after the Iron Horde invaded Azeroth but were pushed and became invaded themselves. Working to dismantle the Iron Horde the champions of Azeroth freed Frostwolf prisoners and with that an act the Horde expedition and the Frostwolf orcs became allies. At the behest of Gan'ar the two turned their attention towards the Bladespire ogres and launched an attack on Bladespire Citadel.
However Ga'nar proved too hasty and led warriors against the Bladespire before the rest of the clan was ready. An action which has split the Frostwolf attack forces, regardless the Horde forces are able to help by first claiming Gormaul Watch. With the watch secured the Horde forces venture deeper and aid in killing Dorogg the Ruthless, countless Bladespire ogres, and helped free the ogre slaves.
With the citadel nearly secure the Frostwolves strike against Gorr'thog, who is slain after a fierce fight. With the ogre warlord dead, the Frostwolves then claim the foretress as their own.
After claiming Citadel Durotan learns that the Thunderlord clan launched an attack on Wor'gol, while the Frostwolves were busy dealing with the ogres. In order to help his prisoner he request the commander and his Horde allies for aid, which is swiftly granted.
Meanwhile with the loss of their citadel, the Bladespire at the Circle of Blood poisoned their gladiators - Frostwolf slaves that they forced to fight one another - in retaliation.