Template:CoT
General
The Dark Portal
The Orcs are setting foot on Azeroth.
- Level: 68-70
- # of Players: 5
- Location: Caverns of Time
- Abbreviation: BM
- Final Boss: Aeonus
- Released: Burning Crusade
- Reputation: 1110~ with Keepers of Time
- Time: It takes about 30 minutes to fully clear the instance, starting from triggering Medivh until the last boss is dead.
History
In this wing of the Caverns of Time, a group of players must defend the last Guardian Medivh, in a swamp known as The Black Morass. The Guardian Medivh, possessed by Sargeras, attempts to open the Dark Portal to Draenor, while wave upon wave of dragonkin of the Infinite Dragonflight attempt to defeat Medivh in order to alter time and halt the invasion of Azeroth from Draenor.
- For the event prior to the release of Burning Crusade, see Dark Portal Opens.
Entry
Completion of Escape from Durnholde Keep and the following quests.
The Sands of Time
[66] To The Master's Lair- [68] The Caverns of Time
- [68] Old Hillsbrad
- [68] Taretha's Diversion
- [68] Escape from Durnholde
- [68] Return to Andormu
[66] 
Creatures of Interest
Encounters
Bosses
Trash
Before the event:
During the event:
- Rift Lord
- Rift Keeper
- Infinite Assassin
- Infinite Whelp
- Infinite Chonomancer
- Infinite Vanquisher
- Infinite Executioner
Walkthrough
Map of the Black Morass
The Black Morass begins with the five players entering the portal in The Caverns of Time. Once inside, it is recommended that the players all pick up a Chrono-beacon from Sa'at before leaving the cave. The instance setting is a swamp which is filled with non-elite beast mobs that must be cleared. A path can be cleared to straight south heading towards Medivh, but it is recommended to clear all trash in the areas where combat will occur during the event. Generally, only the islands and strips of land immediately across from Medivh need to be cleared, though a wider radius is safer until the group has a good sense of where the action will take place. See Map
The mobs can be easily rounded up several at a time by one player on horseback, led back to the rest of the party, and then burned down with AoE attacks.
Once any player enters the area approximately 10 meters from Medivh, the event will occur.
The Opening of the Dark Portal
The event begins with Medivh calling for assistance and a portal quickly opening in one of the four designated zones: the first of 18 total waves of dragonkin of the Infinite Dragonflight. Once a given portal has been shut or enough time has passed, a consecutive portal will be opened in a different zone and the entire encounter is timed from the opening of the first portal. At waves 6, 12, and 18, there is a boss encounter. All of the portals will spawn mobs that will seek to drain Medivh's shield and eventually kill him.
Waves 1 through 5
Each of the first five waves of the event consists of one elite—either a melee-class Rift Lord or caster-class Rift Keeper—that is tethered to the portal, and a stream of non-elite mobs. While the portal is open, adds will spawn every 15 or 20 seconds according to this repeating cycle: 1 Assassin, 3 Whelps, 1 Chronomancer. These adds will head directly towards Medivh, and must be dealt with or they will drain his shield and kill him.
The non-elites all do small amounts of damage, and can be easily killed by any class; AOE is not required, though abilities like frost nova and snare can be useful for managing multiple adds at once. It is recommended, however, that one player focus specifically on the spawning creatures, while all other party members focus on the tethered elite. Frost-specced mages can do quite well at this job or another strategy that works really well is if you have a hunter and mage the hunters pet can be used as a tank for the adds and have the mage burn them down (with this strategy both the pet and mage can stay in range of healer and allows the mage to focus on dps).
Once you destroy the elite in a wave, everyone should kill the remaining non-elites and rest up for the next portal. The key here is pacing: while the next portal will almost certainly have opened before you finish cleaning up the non-elites, it's best to have healers and mana-based DPS classes drink up before they start in on the next rift lord/keeper. The longer you wait, the more adds you will have to deal with and the farther behind you will get on new portals opening, but if clearing the adds is going well, but you need not rush immediately from one portal to another if your group isn't quite ready.
Each portal's elite will proximity aggro, but the adds will not. The DPS assigned to adds can take advantage of this by opening with a spell with a long casting time, e.g. 
[Pyroblast].
Wave 6: Chrono Lord Deja
Health: 89,000
Mana: 33,090
Special Abilities
- Time Lapse – Magic AoE debuff: Attack speed and movement speed reduced by 60%.
- Arcane Discharge - Arcane Damage: Hit all targets in a big range for 2200-2600 damage.
This fight can easily be done by four players, while the fifth defeats the spawning non-elite mobs. Alternatively, you can all dps him down and then use a beacon to clean up the remaining adds. Chrono Lord Deja takes the place of Rift Lord or Rift Keeper that would normally spawn with portal six.
Chrono Lord Deja is an easy fight. The only ability of note is the Arcane Discharge. This is easily healed through, and the party member assigned to deal with the trash headed for Medivh should still be able to do so during this encounter.
After Chrono Lord Deja is defeated, your group should have thirty seconds to a minute of rest before the seventh wave arrives, depending on how fast you killed him.
Heroic: Pulls people towards him, making his chain attacks much harder to avoid.
Waves 7 through 11
Same as waves 1 through 5. Adds spawn according to this repeating cycle: 1 Executioner, 1 Chronomancer, 3 Whelps, 1 Assassin.
Wave 12: Temporus
Health: 110,000
Mana: N/A
Special Abilities
- Mortal Wound - Debuff, cannot be dispelled: Decreases healing on target by 10%, stacks up to 10 times. Lasts 15 seconds.
- Haste - Buff, can be dispelled/spellstealed: Temporus's attack speed is increased slightly and run speed is increased dramatically (+200%).
- Knock Away - Physical Damage, AOE: Knocks back all nearby enemies.
- Untauntable - Temporus cannot be taunted.
You have several options for dealing with his Mortal Wound debuff:
- Have all five members focus on defeating the boss quickly before the debuff stacks to 10, then kill the remaining non-elites after he is dealt with. Warriors can use last stand and shield wall towards the end to try and stay alive: if an off-tank is available, losing the MT towards the end can be an acceptable loss since there will be time to res afterwards.
- Use an off-tank to switch aggro. Switching aggro can be quite difficult, however, because Temporus is not tauntable.
- Try to evade Temporus for long enough that the Mortal Wound debuff wears off. The debuff is applied every six seconds and last 12 seconds. Note: If the tank runs Temporus too far away from the portal, he flies back and resets himself to full health immediately, making a wipe near inevitable.
- Apply a paladin
[Blessing of Protection], switching quickly to an off-tank that can busy Temporus while the debuff wears off.
Temporus is one boss where it is highly recommended to allow the non-elite mobs to pass by, then when Temporus is defeated to drop a Chrono-beacon near Medivh to clean up the remaining mobs. You may need to use beacons at some point just to deal with the amount of adds who have aggroed to the party and are attacking casters. Just be sure not to use the beacon too close to Temporus himself, as it will fail and be wasted.
The Haste buff increases run speed dramatically. Therefore, if your party has a mage spellstealing the Haste buff, then your mage should be the one assigned to drop a Chrono-beacon on Medivh about halfway through the fight. With the Haste buff, the mage can run to Medivh drop off beacon and be back to Temporus all within only 2 global spell cool-downs.
If the group has no mage, a priest can use Dispell Magic on Temporus, a warlock can summon his Felhunter and use Devour Magic or a shaman can use Purge to remove his Haste buff.
Rather than trying to evade and kite Temporus, a protection-specced warrior can tank and spank him. His "Mortal Wound" ability can be blocked and is on a ~6 second cooldown, so timely use of Shield Block can allow it to fall off.
Protection paladins should easily be able to keep up 100% block through the whole fight if the Haste debuff is dispelled.
This fight can get tough with a bear tank, as they don't have a shield and can't block or parry. One method we used to get past it is have a rogue evasion tank Temporus for the first 30 seconds (use Preparation). After than, the bear tank can step in and by the time you've been stacked with 10 debuffs, Temporus is almost dead. Also, if you're a bear and you happen to have a priest in your group, keep the shield up at all times. The druid will be able to keep rage and the shield helps to mitigate the immense damage. On a side note, Frenzied Regeneration is unaffected by the debuff, so use it to make the last stand if necessary.
Heroic: Has a 6 second duration spell reflect.
Waves 13 through 17
- Waves spawn at an accelerated rate, sometimes with as little as one minute between portals.
- Adds spawn according to this repeating cycle: 1 Executioner, 1 Vanquisher, 1 Chronomancer, 1 Assassin.
- Due to accelerated rate, it might get tough for the designated add-dealer to take all the incoming waves. One possible strategy is to stop going after the Rift Lord or Rift Keeper at around wave 15 or 16 and just have the whole group at Medivh, taking out adds, while ignoring the elites. The non-elite adds stop spawning when the final boss comes - and you still have plenty of time to drink before engaging. It is possible to simply proceed as before however, especially if you have several beacons left. You can safely burn all of the beacons on the last round of adds prior to the appearance of the boss.
- Aeonus will likely spawn before the last Rift Lord is dead: simply ignore this and finish off the portals and the adds.
- When DPS is low (indicated if more than 4 adds are getting through each wave between waves 1 to 6), use one beacon to clear up adds after Temporus, leaving the group with a remaining 4 beacons. Assign a beacon at the wave 14, 15, 16, 17. Place the beacon not where Medivh is, but where the Rift Lords are to bring them down faster and to handle incoming adds. After wave 17 is down, drink and eat up. Medivh's shield should be able to take a beating until the group is ready to tackle the last boss.
Wave 18: Aeonus
Health: 150,000
Mana: N/A
Special Abilities
- Time Stop - AoE Debuff: Stuns all players for four seconds.
- Sand Breath - Nature Damage: Deals 3000 damage with a cone in front of Aeonus.
- Frenzy - Buff: Increases Aeonus's attack speed. Can be countered with a hunter's tranq shot.
The final boss and wave of the encounter, Aeonus spawns alone. He will immediately head towards Medivh and attack him. If Medivh's shield is in respectable condition, it is recommended that the party to rest up before the battle. Tanks can put on some nature resistance gear get a NR aura, but avoid sacrificing too much armor or stamina for it: the sand breath is trivial compared to the damage he can deal while healers are stunned.
Besides his abilities, Aeonus hits for very high amounts on any players. This is compounded by the Time Stop ability, causing Aeonus to continue to attack the highest aggro target while healing is unavailable. If healing is kept at a maximum, Aeonus will quickly fall to focused dps.
Why should the Alliance help?
Some have questioned why the Alliance should help Medivh in opening the Dark Portal. After all, it was the opening of the Dark Portal that triggered the First War and the collapse of the Kingdom of Azeroth (not to be confused with continent of Azeroth). If the Dark Portal was never opened, Azeroth and Draenor would have never been bridged. The Orcs would have never arrived, and the Horde would have never been formed. Chrono Lord Deja of the Infinite Dragonflight claims that "many lives could be saved" and "the resulting wars could be erased".
However, if the Dark Portal was never opened, it is explained by the Keepers of Time that the Alliance would have never formed. Instead, the races that form the Alliance would have descended into a chaotic civil war. Azeroth would have then been mercillessly crushed by the invasion of the Burning Legion. The Burning Legion would have then initiated an act of mass genocide, effectively destroying all life on Azeroth. This would have resulted in many more deaths than the First War and many others combined. Therefore, preserving time and opening the Dark Portal can be seen as "the lesser of two evils".