War in Draenor

The war in Draenor is a conflict spanning two worlds in separate timelines. The conflict seeped into the original timeline's Azeroth in 31 ADP because of Kairozdormu's meddling with timeways. The bronze dragon has sent Garrosh Hellscream 35 years ago to the past of an alternate, some time prior the Blood Pact, with a mission to prevent the orcs from drinking Mannoroth's blood and create an uncorrupted Horde for Kairoz's own purposes. However, Garrosh betrayed Kairoz, with no intentions to serve another "puppet master" and stole his fragment of the Vision of Time, which he used to convince Grommash of the cruel fate of the orcish race, should he drink the demon blood. With the information gained through the artifact and Garrosh's knowledge, the orcish clans have united into the Iron Horde, a militaristic and technologically advanced union under the leadership of Grommash, supplied by the goblin Blackfuse Company, bent on the path of total conquest and dominion over the universe. The Burning Legion, enraged by the turn of events began their own campaign against Draenor as well, aiming to salvage as much of the original plan as possible, including the destruction of Draenor.

During the war, the Alliance and Horde were technically under a peace treaty, but the Horde broke it at Ashran.

Garrosh's trial
After the defeat of Garrosh Hellscream, the Alliance and Darkspear Rebellion have agreed to hand the overthrown warchief to the hands of Shado-Pan, who were going to move him to Pandaria where he could be tried for his war crimes committed during the Alliance-Horde war. However, before the verdict could be announced, Garrosh was able to escape through a time-space gateway with the help of a bronze dragon, Kairoz.

The portal has brought him to the alternate Draenor, decades before the current events, where he was able to set up a chain of events convincing Grommash to distrust, in order to prevent a crucial moment in the universe's history: the corruption of the orcs through the Blood Curse.

At some point the Blackfuse Company arrived to Draenor with their brand siege weapons to reinforce the orcish clans.

Message to Gul'dan
Gul'dan sent a message to the orcs promising them untold power. Already warned by the younger Hellscream about the dark plot, Grommash sent him in reply, disguised as a messenger, to Gul'dan wishing to know more about his plans. Gul'dan told Garrosh that he had seen a vision, and a Legion wanted the orcs as their vanguard. Much to Gul'dan's surprise, Garrosh knew serving this Legion meant entering the Blood Pact by drinking the blood of Mannoroth, which would bind the orcish race to serve the demons. Angered at Garrosh's accusations of slavery, and proclaiming himself to be a god, Gul'dan had his guards remove the messenger from the premises. In response, Garrosh slew the guards. Gul'dan told Garrosh that in three days the orcs would drink from Mannoroth's blood on a mountaintop in Tanaan Jungle and from there march to victory. Garrosh lowered his hood, revealing his identity, and told Gul'dan that in three days Grommash will stand on the mountain as well and lead the orcs to embrace their true fate.

The clans assemble
Garrosh and Grommash set about gathering the clans and building their own Dark Portal in Tanaan Jungle. The led by  took to the new technology Garrosh brought with great interest, building larger and more powerful war machines including the Iron Worldbreaker. of the Shattered Hand, the of the,  with Dharl, and  of the Bleeding Hollow also joined the Iron Horde. Two clans however, the Frostwolf Orcs and the Laughing Skull Orcs refused, with the latter not wanting to submit to anyone's rules, and the former not wishing to participate in pointless conquest. 's eventually joined as well, giving the Iron Horde the Dark Star's power of the void and necromancy.

Shortly after the Iron Horde's formation, Grommash ordered an attack on Highmaul, seat of Imperator Mar'gok. The emperor had no other option than to negotiate with the warchief. Upon agreeing to train orcs the magic immunity, the attack ceased and the ogres became Iron Horde's allies.

The Iron March
Using the dark power of the members including, the new red Dark Portal successfully opened into Azeroth. Garrosh's invasion force led by Commander Tharbek stormed through the portal and began the Iron Horde Incursion, led by Warlord Zaela. The unexpected invasion quickly destroyed all Alliance and Horde resistance in the Blasted Lands including Nethergarde Keep and Dreadmaul Hold. Zaela took a battalion of warriors and quickly flew to Blackrock Mountain to begin construction of a super iron star that would destroy Stormwind City. Archmage Khadgar quickly warned both sides of this massive threat. The Alliance and Horde united to destroy the Iron March and push the invaders back through the portal. A number of Azeroth's great heroes joined the battle, including Khadgar, Lady Liadrin, Thrall and Vindicator Maraad.

Skirmish in Tanaan
The united front succeeded in pushing through the portal, but once on the other side, it was apparent that the numbers and power of the Iron Horde were utterly overwhelming. After encountering each of the Iron Horde's warlords (with the exception of the and Dharl), the Draenor expedition used hit-and-run tactics against the orcs to stay alive. In addition, they saved several important figures including Farseer Drek'Thar, Exarch Maladaar, Ga'nar and Yrel the priestess. The expedition came to the conclusion that if Azeroth was to be safe from the overwhelming power of the Iron Horde, the must be destroyed and the threat must be ended in Draenor. Using the Blackrock's Iron Worldbreaker, Thaelin Darkanvil destroyed the portal and Khadgar led the remaining Alliance and Horde forces to safety on the Iron Horde's battleships. The expedition then split, with the Horde heading north to recruit the Frostwolf clan and the Alliance going south to request the aid of the Council of Exarchs.

Shadowmoon Valley: the Prophet and the Dark Star
The Alliance expedition, led by Vindicator Maraad, landed in, where most of the draenei of Draenor call home. From Lunarfall, the Alliance struck out against the Shadowmoon clan. The Shadowmoon showed they are using the power of the "Dark Star" to harness the power of the void to summon void creatures and cast powerful magic at the cost of the corruption of their own souls. Draenor's versions of and Akama aid the Alliance in their endeavors to settle in Shadowmoon and combating their enemies. The Council of Exarchs, however, suffers betrayal from within, openly from Exarch Othaar and more subtly from Soulbinder Nyami. Both believe Velen has led them to ruin and allied themselves with the Burning Legion and their minions, the Sargerei. Velen eventually learns that Ner'zhul plans to summon his ultimate weapon, the Dark Star, directly to Draenor and use its dark power to utterly end the draenei once and for all. Despite Velen and the now-paladin Yrel's best efforts, the Dark Star descends, forcing Velen to make the ultimate sacrifice to purify the dark entity in, revealing it's true form: K'ara the naaru. With the power of the naaru flowing through them, Yrel and Maraad decimated the Iron Horde forces as they marched on the draenei capital of Karabor. Ner'zhul retreats to the Shadowmoon Burial Grounds where he meets his death, ending the threat of the Shadowmoon clan.

Frostfire Ridge: the Frostwolf brothers
The Horde expedition, led by Thrall, landed in Frostfire Ridge. Drek'Thar vouched for the strangers who saved both his and Ga'nar's lives to the Frostwolf chieftain and his mate. Vol'jin's Horde proved themselves in Durotan's eyes when they helped the Frostwolves take Bladespire Citadel, a massive ogre castle which would serve as the Frostwolves new fortification against the oncoming Iron Horde. The Thunderlord clan, led by the orc known as the Iron Wolf, began making raids against the Frostwolves using powerful subjugated gronn and rylaks. Durotan's brother Ga'nar led the charges against the Thunderlord aggressors, their allies proving to be more than a match for the Thunderlord beast masters. Finally, the Iron Wolf fought Ga'nar and Durotan face to face, revealing that he was in fact their oldest brother, Fenris Wolfbrother, who broke away from the Frostwolves, believing they should not be equal to beasts or other orcs, but that they should subjugate all others to their will. The wayward Frostwolf met his end at the hands of his younger brothers as Grommash's forces began to invade Frostfire Ride through Thunder Pass. The Horde and Frostwolves clashed with the invaders in the Battle of Thunder Pass, with Ga'nar heroically sacrificing himself to buy Drek'Thar time to seal the pass. With the Thunderlord pacified and the Iron Tide stemmed, Frostfire was secured.

Gorgrond: gaining allies in the savage land
After securing Shadowmoon and Frostfire, both sides sent their heroes to secure a foothold in Blackrock clan territory: Gorgrond. Yrel leads the Alliance in gaining the help of additional Rangari rangers while Durotan and Draka make an alliance of convenience with the Laughing Skull clan led by Kaz the Shrieker. Depending on the choices made by the player, the expeditions endeavors will provide additional resources from Gorgrond's jungles or several warriors of Gorgrond's wastes including Rexxar. If the players battle the botani, they kill the Genesaur Iyu and take an artifact that lets them control genesaurs, or fight the subjugated gronn forces of the Iron Horde and gain an artifact that controls magnaron. The Iron Horde wished to use these artifacts for their own conquest, but Yrel/Draka suggest using this power against them. The Alliance/Horde assault the Blackrock fortress, the Iron Approach. With the power of the artifact, the Iron Horde forces under Commander Gar were destroyed by the very power they hoped to control. With a serious, though not fatal, blow dealt to the Blackrock clan, the Alliance/Horde forces receive requests for aid from their forces in Talador.

Talador: The Burning Legion and the Iron Horde
In Talador forest, a massive Iron Horde fleet led by and  sails toward the draenei capital of. After dealing with some Gorian ogre mages and establishing their outpost, as well as receiving aid from Khadgar and his Kirin Tor forces, the Draenor expedition deals with the Iron Horde. Yrel and Maraad halt the Iron Horde's advance through the forest, while Durotan heads north to try to reason with Orgrim, the orc he once considered his sworn brother. Despite the Frostwolf Chieftain's best efforts, Ogrim stands firmly loyal to the Iron Horde. Using a prototype goblin shredder, the expedition destroys the remainder of Orgrim's ground forces, leaving only Blackhand's battleships and warriors. As Blackhand's fleet arrives at Shattrath, Khadgar leads a united attack against the Blackrock warlord's army in the Battle for Shattrath. As Blackhand readied his battleships massive cannons to destroy the city and all it's inhabitants, Doomhammer objects, claiming he will not stand by while the innocent of the city are slaughtered. Khadgar and Thaelin Darkanvil take Blackhand's ships while the remaining heroes battle Blackhand. Blackhand easily defeats them all in a massive explosion, killing Orgrim and Maraad. Luckily, Yrel and Durotan are able to pummel Blackhand long enough for Khadgar to destroy their ships and teleport his allies to safety. Blackhand gets away and Shattrath is saved, for now.

Meanwhile, under Teron'gor had succeeded in summoning a small army of demons of the Burning Legion. As commanded by Gul'dan, Teron'gor set his sights on, a sacred graveyard whose powerful souls could be used to strengthen the Shadow Council and their demon masters. Lady Liadrin, having experience fighting demons, aids the Auchenai under Exarch Maladaar in battling the legion and council forces with her Sunsworn force. The united army of the Auchenai and the Blood Knights receive further aid from Astalor Bloodsworn's new Blood golems as well as from ancient gorian ogre spirits. As Teron'gor's army is defeated in Gul'var, he retreats to Xandros. Liadrin and Maladaar accompany the adventurer and slay the pit lord Mongrethod. However, Teron'gor had one last plan in place: the Sargerei who had infiltrated the Auchenai within Auchindoun. With their treacherous aid, he broke his way into the heart of Auchindoun, his demonic servants killing numerous priests and paladins. Teron'gor and his forces were thwarted, but the status of the mad warlock remained unknown. The remaining Sargerei and Shadow Council forces then went to Shattrath and served Socrethar who managed to summon more demons and they controlled the city for some time. The city was presumably retaken following Socrethar's death. The remainder of the Iron Horde forces in Talador retreated to Bladefury's Command to guard the path to Hellscream's fortress in Tanaan.

Spires of Arak: the arakkoa schism
With the Legion and Iron Horde forces defeated in Talador, the Draenor expedition looked south to gain the aid of the arakkoa in the Spires of Arak. Admiral Taylor's forces were the first to establish a garrison in Arak. As Taylor's forces set out to create their garrison, Taylor noticed that his follower Ephial was obsessed with ley lines. When a group of lumberjacks disappeared, Ephial, Nas Dunberlin, and a few of Taylor's men went to clear the area of wasps. A few days later, the Iron Horde attacked their garrison. Although they fended off the incursion, Ephial went missing after the fighting but subsequently returned. Wrathion later sought asylum at Taylor's garrison. Taylor agreed to protect Wrathion from the ogres he offended so long as Wrathion remained under house arrest and full-time guard. Wrathion would continue to provide resources to Taylor's garrison and cryptically told Taylor to keep an eye on Ephial. When Taylor left to participate in the Ring of Blood arena battles, Ephial and his cultists took control of the garrison. After Taylor returned, he found the garrison overrun by the traitors and Wrathion gone with some of his best followers. While Taylor told his loyalists to save who they could from the defectors, Taylor went to face Ephial personally. Sometime later, the Alliance and Horde commanders soon came to the Spires of Arak to establish Southport and Axefall respectively. While the Alliance went to re-establish contact with Taylor's garrison and create a supply line between the two bases, the Horde sought to plunder it when they saw it was seemingly unguarded. The heroes soon discovered that Ephial was a necromancer and his death cult infiltrated Taylor's forces and turned Taylor's entire garrison into undead spirits. The adventurers went on to dispatch Ephial's cultists and undead, and met up to rescue Admiral Taylor at his farm. Ephial however, had transformed Taylor into the Bone wraith Soulscythe. The adventurers destroyed Soulscythe and slew Ephial, freeing Taylor and his loyalists from the dark magic that haunted the garrison. The commander's companion guided Taylor's spirit back to Southport but rather than retire to his due rest, Taylor decided to continue fighting at the Alliance commander's side as their follower.

After witnessing the brutality of the Adherents of Rukhmar and their hatred of any who are not of their cult of Rukhmar, the expedition allied themselves with the Arakkoa Outcasts. Led by Shadow-Sage Iskar and protected by their patron raven-god, summoned thanks to Iskar's mission in Talador to get The Eye of Anzu, the outcasts were being persecuted and slaughtered by the fanatical adherents. To make matters worse, and his Shattered Hand clan began encroaching on the Spires as well. Using stealth, guerilla tactics and sabotage as their greatest weapons, the outcasts and their new allies made significant strikes against the adherent forces. One among the outcasts, Reshad the storyteller, was able to complete the ritual to summon the weakened spirit of the ancient hero-king of the arakkoa: Talon King Terokk. The power of the Talon King was used to decimate the Shattered Hand forces, though Kargath himself managed to defeat Terokk and escape. Afterwards, Anzu sent the adventurers to the Ravenspeaker cult, a small group of outcasts, and they managed to summon Anzu's consort Ka'alu, gaining the aid of a large flock of dread ravens. With their new numbers and powerful allies, the outcast forces assault the remaining adherents at the spires near Skyreach. The battle for the spires ended when the adherent leader High Sage Viryx was killed in Skyreach.

Nagrand: Garrosh's last stand
With the victory against the mad arakkoa behind them and the Iron Horde's power diminishing across Draenor, the Alliance/Horde expedition set their sights on the one responsible for the war: Garrosh Hellscream. The expedition receives word that Grommash had promoted Garrosh to Warlord of the Warsong clan while Grommash is in Tanaan, in addition to giving him his personal weapon, Gorehowl. Thrall and Yrel personally lead the expedition forces into Nagrand. After establishing bases for cavalry and Steam tanks/Demolishers, the expedition first decided to weaken the Warsong clan's allies, the and the Gorian ogre mages, before going after Garrosh. The disgraced blademaster Lantresor of the Blade allied himself with the expedition adventurers and together they battled the Burning Blade. The clan's warlord was slain, only for his position and blade Sanketsu to be taken up by his daughter: Azuka Bladefury. Azuka banishes Lantresor before retreating for now. The ogres at Mar'gok's Overwatch, researching and creating a new breed of ogre mages known as "breakers," were also dispatched, some of them retreating to the ogre capital of Highmaul. The fallen draenei town of Telaar was liberated from Warsong raiders with the help of Shadow Hunter Kajassa and the forces from Telaari Station. Durotan then leads an attack on the Warsong stronghold of Lok-rath. At first it appears to be a decisive victory, with Uruk Foecleaver declaring that he surrenders. However, this was a ruse and the deceptive Warsong attack when the expedition forces have their guard down. After a bloody battle, Lok-rath's orcs were dealt with.

In the meantime, and Vindicator Nobundo worked with Throne of the Element's Furies to calm the elements on the north and discover the whereabouts of Gordawg. It was discovered that 's lackey - - had gained control of the pale orcs, Gordawg and the naaru K'ure. Though the two fought their way to, they were unable to safe any of them with Cho'gall taking K'ure's power to himself, betraying Gul'dan and leaving for an unknown destination with the rest of the pale orcs. While Gordawg was killed, his ghost returned to the Throne. During this time, Warsong shamans also pulled the Void creatures from the Twisting Nether. The shamans were stopped before they could cause any further chaos.

With the Warsong's allies subdued and their forces routed, the expedition set their eyes on Garrosh's seat of power in Nagrand: Grommashar. Thrall, Yrel, Durotan, Draka, Aggra, and Rangari D'kaan destroy the gates and charge within. The Warsong prove difficult opponents, retaliating with packs of worgs, Dark shaman, and even the subjugated Durn the Hungerer. As the Iron Horde forces continued to fall, Durotan/Rangari D'kaan and the commander break into Garrosh's hold and engage him directly. Garrosh shows that time had not dulled his edge and uses Grommash's weapon Gorehowl in conjunction with chain-weapons to subdue his enemies, but they are saved when Thrall arrives and challenges Garrosh to one last Mak'gora. Garrosh, proud as ever, agrees and claims the sight will be the Stones of Prophecy, the future sight of Garadar where Garrosh's journey with Thrall began. A fierce duel ensues, with Garrosh claiming Thrall made him what he is. Thrall denies this, claiming Garrosh chose his own destiny before using his shaman powers to electrocute Garrosh to death. The Warsong were defeated and the war criminal Garrosh was finally brought to justice. But despite his death, the war was far from over.

Highmaul
After the commander was promoted to general, the expedition planned to finish off Grommash's ogre allies at Highmaul. Having proved their worth in the Ring of Trials, the Alliance/Horde forces fought in the Highmaul Arena's "Battle of Red Spires," where Grommash and Kargath were in attendance. After dispatching Vul'gor, himself sought to pay back the adventurers who had insulted him back in Tanaan. Using the arena's traps against him, the Shattered Hand warlord was slain. used this opportunity to break into the city and use his new army of Pale orcs to assault Highmaul, wishing to gain Imperator Mar'gok's magic runes for himself. Both the pale orcs and ogres suffered heavy losses as the adventurers fought their way through the city and into Mar'gok's sanctum. In normal difficulty, Mar'gok simply uses the runes to empower himself and dies despite all his power and guards. In mythic difficulty, Cho'gall is able to breach the sanctum and successfully absorbs Mar'gok's power, killing him. The mad ogre mage attacks the party with the void magic gained from K'ure, shouting rhetoric of the "infinite night" strikingly similar to his Old god-corrupted counterpart. Cho'gall falls and delivers an ominous warning that "He comes... you can never escape..."

The Garrison Campaign
Rokhan, Vol'jin's chief scout, and Bodrick Grey receive word that Azuka Bladefury has joined the Iron Horde and will be meeting with Grommash at a council. The general clashes with the Burning Blade warlord, the duel ending in a draw. The expedition and the Burning Blade then race to gain the Heart of Gorgorek, a titan artifact that can control the mightiest and oldest magnaronn, Gorgorek. Azuka eventually succeeded in gaining the artifact and awakening Gorgorek, planning to use the magnaronn to spearhead an Iron Horde assault on Talador from the Gates of Tanaan. The expedition's garrison forces and followers intercept the Iron Horde before they can launch their attack. Using rylak riders, the commander felled the mighty magnaronn and fought Azuka one last time. Azuka showed the true power of her sword Sanketsu, the ability to grow stronger with every life it takes, by killing her own Burning Blade initiates. The Burning Blade warlord finally met her end as her clan watched in disbelief. As expedition forces finished mopping up, they saw the gates to Tanaan were far too fortified to take at that moment. Despite Grommash's taunts, Durotan/Yrel back off to fight another day, vowing to take Grommash's life when the time is right.

Blackrock Foundry
Keeping up the momentum of their victories against the Iron Horde, the expedition forces assaulted Blackrock Foundry, the place where the clans received most of their weapons, armor and siege weapons. The foundry was protected by champions of the different orc clans, such as Flamebender Ka'graz of the Burning Blade, and Beastlord Darmac of the Thunderlord. As the raid found their way to Blackhand's Crucible, Blackhand used all his remaining strength, weapons and mastery of fire, but was overwhelmed. Without the Blackrock Clan's weapons, Grommash's Horde was greatly weakened.

Gul'dan Ascendant
As Grommash's Horde continues to fall apart around him, of the  was one of the few who remained at his side, though the Bleeding Hollow began to show signs of discontent. It was at this time that Gul'dan made his reappearance at the gates of Tanaan Jungle. The warlock attempts to break Grommash's spirit by reviewing his Horde's failure, revealing Garrosh is both dead and was his son. He offers the Blood of Mannoroth once more, claiming it is the only thing that can save the orcs now. After refusing, Grommash is restrained by Gul'dan's powers. Kilrogg however, knowing his own eventual fate, was indeed willing to drink the fel blood, transforming him into a demonic monstrosity. With Grommash captured and the remaining orcs under his command, Gul'dan prepares for the arrival of his demon masters.

Tanaan: Fury of Hellfire
Gul'dan uses the corpse and blood of Mannoroth to channel a spell that corrupts Tanaan and shares the blood with those loyal to him, creating the Felblood orcs, as well as rallying several arakkoa from of the Adherents, Outcasts and Sethekk with the promise of flight including Shadow-Lord Iskar, and the remaining Sargerei. He travels to and creates a demon portal called the Black Gate to bring forth the full force of the Burning Legion. While Durotan and Maladaar lead a frontal charge through Talador, Draka and Yrel use the newly constructed shipyards to establish a foothold on the eastern side of Tanaan. They organize various attacks to weaken the enemy forces.

In the meantime, the enemy launched several attacks, such as Sargerei's final attack on Auchindoun, this time to locate Teron'gor. With the help of Drek'Thar, Yrel and the recently defected Oronok Torn-heart, they stop Gul'dan from using the Cipher of Damnation on Cyrukh, preventing the tragedy that happened in the prime-timeline's Shadowmoon Valley.

The united forces, led by Khadgar, charge into Hellfire Citadel, destroying all the powerful demons, corrupted orcs, and aberrations the Legion laid before them, including the now-corrupted Iskar, Gorefiend, Kilrogg Deadeye and the resurrected Mannoroth. The adventurers also free the captured former Warchief, Grommash Hellscream. In the end, the heroes of Draenor and the expedition, Yrel, Durotan, Khadgar, and even the defected Grommash, came together to slay Archimonde. With his dying breath, Archimonde, stating they had a pact, sends a fel blast to Gul'dan, sending him through the Black Gate as the eyes of Archimonde dims. Grommash concluded that now Draenor is free. While Khadgar acknowledges that the war with the Burning Legion itself is far from over and that they must return to their own timeline, Yrel assures him that if they ever have need of Draenor's heroes, they will be there. Khadgar flies off as Yrel, Grommash, and Durotan vow to rebuild Draenor.

Khadgar's campaign
While the Alliance-Horde expedition was mostly busy dealing with the Iron Horde, Archmage Khadgar, feeling responsible for the release of Gul'dan after the Assault on the Dark Portal, leads agents of the Kirin Tor to track down the mad warlock. While Jaina Proudmoore opposes the Horde, the pragmatic Khadgar accepts their aid. He forges a powerful magic ring to aid the commander against the Iron Horde and Gul'dan's forces. While besieging Highmaul, the adventurers brought back Abrogator Stones to help track down Gul'dan, but his help is requested by Chromie to help track Kairozdormu, the cause of entire war. It is revealed that Kairoz was killed by Garrosh shortly after arriving on Draenor and his spirit is fought. Gul'dan was not blind to Khadgar's plans, however, and sent his best assassin:. Nearly successful in killing him, Garona is captured by the adventurer and Khadgar's bodyguard Cordana Felsong. Using the Elemental Tablets from Blackrock Foundry and a Shadow Council Orb of Domination, Khadgar frees Garona from Gul'dan's mind control. Eternally grateful, Garona swears her life to the commander. Together, they witness Gul'dan's meeting with Grommash and Kilrogg. With Gul'dan now in command of the Iron Horde, the trio retreats to regroup and strategize. After the general builds the shipyard, Khadgar requests that they bring down Gul'dan's flagship and confiscate Gul'dan's library of chaos magic. After finishing these, it is revealed that Cordana was corrupted by Gul'dan from afar by the Orb of Domination, seduced by his power. The general is forced to put Cordana down, but she was able to stun the general and create a demonic portal to escape. Obtaining more knowledge for Khadgar has gained helps him increase the magic ring he gave the general to it's maximum potential. He later proceeds to aid in the final battle with Archimonde before returning to Azeroth.

Primals versus Breakers
In Gorgrond, the forces of Primals and Breakers are locked in an eternal battle.

The Kirin Tor wanted to maintain their own link between Stormwind City and Draenor, building a portal in the Everbloom and drawing attention of the primal forces. The botani and the genesaur Yalnu attacked and corrupted Violet Bluff and turned on to the portal. Once the genesaur entered Azeroth, he was put down by the remaining mages and the adventurers of the Alliance and Horde.

Ashran
The forces of the Alliance and Horde camped in the south and north respectively of Ashran. The Iron Horde has no presence on the island but the ghost of ogres control several locations.

The Alliance is seeking a specific, large artifact, theorized by Harrison Jones to have powers rivaling that of titan technology. The artifact appears to have military applications, with the possibility of using it or the knowledge gained from it against the Horde. The Horde are aware of the Alliance's search, and are attempting to find it first in order to defend themselves, breaking their treaty with the other faction and attacking it in the process.

Speculation
While not directly stated, although previously hinted to be the only way, Garrosh likely used the final shard of the Vision of Time to link the alternate Dark Portal to the Dark Portal on Azeroth.

When and how exactly the Blackfuse Company entered the alternate Draenor is unclear. It could be during the Ironmarch invasion when the orcs controlled the Portal.