Betrayal and the Destruction of Alterac The Betrayal and the Destruction of Alterac was a decisive battle of the Second War , during which the Alliance of Lordaeron punished the Nation of Alterac for betraying it . Briefing . " Lord Lothar sends word that the Alliance has been betrayed . Lord Perenolde - sovereign ruler of Alterac - has been working with the Horde since the beginning of the war . " " It was Perenolde who provided the Orcs with the routes of the Elven strikeforce passing through Tarren Mill . " " The rebellion at Tyr ' s Hand was also started by Alterac spies in hopes of concealing the Orcish mining facility located there . " " The High Command has decreed that the nation of Alterac has committed treason against the Alliance and their union with the Orcish Hordes must be broken . " " You must free those unjustly held by Perenolde and enlist their aid in launching an attack against Alterac ' s capital . " Background . Having interrogated the treacherous warriors of Alterac , and discovering that the Alliance had been betrayed , Lothar sent Milan ' s force , and others to Alterac . Rescuing the captive mages and peasants was of paramount importance , for Milan ' s force had no workers and no gold to train them . They formed a standard land attack group of knights and ballistas , then set out on the north road leading to the compound . Getting in was troublesome , but not difficult , since their ballistas had a slightly greater range than the enemy towers . After breaking in and freeing the captives , they sent most of the force back to town , but not before destroying all they could . With workers plundering the mines , they then began fortifying the town with towers and farms , closing off all the paths but one for their troops to use . Next came the construction of stables for their knights , and soon after , the fortification of their keep into a castle . Since their attack plan required only paladins and ballistas , their final construction was a church , and from then on , they concentrated on producing the necessary military units . Time and gold were also spent on the blacksmith , to provide the best possible weapons and armor . When they had gathered nine paladins and four ballistas in the courtyard , their force was deemed ready to make the assault . Moving out to the northeast , their paladins lead the way for the slower ballistas , occasionally stopping to wait impatiently for them . At first they met with only a few enemies , but as they drew near the walls of the capital , greater numbers of Horde and traitorous human forces slowed their progress considerably . After they had leveled several towers and secured an open area within the walls , reinforcements were called for and sent out while the paladins practiced their healing arts on the wounded . Following the advice of their spies , they decided to march north along the inside of the west wall , taking out towers along the way and ignoring lesser structures until later . Soon they were inside the heart of the capital , but they had taken a great deal of punishment . Still more paladins were called for , and before long , they had their revenge on Lord Perenolde . Aftermath . With the destruction of Alterac the Horde had to retire their forces from Lordaeron , the pass through the Alterac Mountains was closed by Stromgarde warriors and at least half of the Blackrock clan was cut off from the rest of the Horde . The Horde had invaded the capital city but without more reinforcements from Alterac Mountains and without the support of Alterac they started losing the battle . And with the betrayal of Gul ' dan simultaneously with this defeat , Orgrim Doomhammer didn ' t have choice but to retire . The battle was not the end of the Alterac collaboration with the Horde . After the Dark Portal was reopened , Alterac spies stole the Book of Medivh from New Stormwind , taking advantage of an assault by the forces of Shadowmoon Clan led by Teron Gorefiend and the Clan ' s " Slayer " . The Book was taken by an Alterac Mage but was later given to Ner ' zhul in exchange for military aid against Lordaeron and Stromgarde forces . The criminal organization known as the Syndicate was also formed by survivors of Alterac .