Thirsty River (mission)

Objectives
Annihilate the opposing enemy teams.
 * Defeat Goss Aleessh's team.
 * Defeat Issah Sshay's team.
 * Defeat Hessper Sasso's team.
 * Defeat Josso Essher's team.
 * Defeat Lyssha Suss's team. (Note: The boss in this team is Custodian Phebus)
 * Defeat Kesskah Shissh's team. (Note: The boss in this team is Custodian Hulgar)
 * Bonus Cleanse the area before King Khimaar's spirit is driven away.

Primary
The idea of this mission is to defeat the aforementioned six teams in three arenas. In the first arena you will meet one team; in the second arena you face two teams; finally you have to fight three teams. Each opposing team is varied in number and formation, but will have one boss (after whom the team is named) and one priest who resurrects fallen team members.

For starters, it is recommended that you kill all 5 Sand Giants on your way to the opposing teams, which will give you a 10% morale boost (2% from each giant). The Sand Giants are at the locations marked with A on the map.

Continue on the obvious path forward, mostly south towards a passage over a wrecked ship. A few Rockshot Devourers should be in your way. Continue along the path over the ship and you'll fight another set of devourers, and soon make your way into an oasis of sorts.

Talk to the Ghostly Hero to begin facing the first boss team, and a timer will appear. The timer is not counting against you: it is actually an excellent tool to time your attacks.

Each team has three groups. Focus on one group at a time. It can be useful to put health degeneration hexes or conditions on each mob immediately, as they can do quite a bit of damage while you kill other mobs in the group. At each multiple of two minutes (2:00, 4:00, etc.), the Enemy Priest, if still alive, will resurrect all his fallen teammates. You need to make sure you kill the enemy priest before the timer hits a multiple of two minutes. Then the team is defeated (the popup says 'annihilated') once you have killed the last of its members. One of the issues with the priest resurrecting these fallen enemies is that they spawn in his shrine, making it harder to kill him.

The usual scenario is to take out two groups blocking your way, then have the entire team break through and kill the priest. If you are too slow in killing the earlier mobs, you may have to rush in to attack the priest while a couple other mobs remain, and then return to the remainder of the enemy team. A good rule of thumb is to begin the concerted attack on the priest at around 1:30 (and for later teams, 30 seconds before a two-minute interval, i.e., 3:30, 5:30, etc.). Sometimes it is necessary to flag henchmen or heroes within range of the priest, so that they do not stop short and attack something else instead.

Tip: If you are worried about being unable to finish off a priest before he revives his fallen comrades (timer nearing a multiple of 2 minutes), then retreat. The revived patrols will move out and you can engage them again. Running in and desperately trying to throw everything at the priest, only to be caught in the respawn, is a sure way to fail. Regrouping and redoing a team is easier than restarting a mission.

The fight in the next arena is against two teams, so you should focus on one team at a time. The Ghostly Hero will open the door to the arena when he nears it. When the door is opened and you enter the arena, enemies will approach you from both sides. Do not fight both teams at the same time; instead, stick to the left wall and engage the team on the left (southeast, labeled E2 on the map). Although it may not look like it, you can avoid aggro-ing the team on the right simply by hugging the left wall. You may want to wait until just before 2:00 before actually initiating the fight, though if your team has decent damage, this is not usually necessary. Forgotten Arcanists cast Kinetic Armor and Ether Renewal, but are far more vulnerable if these enchantments are interrupted or removed.

After finishing the first of the two teams, wait until the timer is near a two-minute interval (4:00, 6:00, etc.) before proceeding to the next team.

Tip: When moving on to a second or third team in a single arena (i.e., while the timer is still going), judge your team's ability to take down an enemy quickly. You may be able to 'cheat' a bit and engage the next team at anywhere from 10 to 20 seconds before an even two-minute interval, as long as you do not drop the first enemy before the two-minute interval is reached. Note that casters will fall quicker than Forgotten Champions.

Continue on to the last arena against three teams, again focusing on and taking out one team at a time. Kill the team at E6 first, then proceed to E4, and then to E5.

The boss at E4 is Josso Essher, a monk. He is an exceptionally good healer. The boss and priest are also linked to a Forgotten Avenger. The priest needs to die first, since trying to kill the monk boss first is likely to fail, as it will probably drag the battle beyond the next multiple of 2:00. While it is possible to kill the priest over the boss's healing by focusing fire on the priest, it is sometimes easier to have one party member distract the boss while the others focus on the priest. If there is anyone with interruption skills equipped (like Cry of Frustration or Distracting Blow), they should try to disrupt the boss as much as possible.

General Tips: Don't rush. Unless specifically going for the bonus, the total amount of time spent fighting is of little consequence, other than the 2:00 minute interval resurrection. Aggroing too many enemies at once is a very easy way to get defeated - especially as party size is limited to 6. Wait for patrols to spread out and take them on, one group at a time.

Bonus
Note:  The King now gets attacked 10-20 seconds after you go in and will be killed in less than 1 minute if you do not rush to save him. The bonus objective is to clear all the enemy teams before King Khimaar leaves or dies. You will know that the bonus is still achievable if King Khimaar is standing in the central area of the third arena. If he leaves before you finish, then you've failed the bonus. The bonus is also failed if King Khimaar dies at any time. If you have any human Monks on the team, make sure they heal the king if he happens to fall under attack. To protect the king, it is best to kill first the team of the warrior boss, Custodian Hulgar.

After you defeat all the teams (in any order), you will receive the bonus 1000 XP, right before the mission ending cut scene.

Hard mode
Rockshot Devourers have Barrage, so a group of five of them at a time can deal impressive damage if you don't spread out. The many traps that the devourers lay can even get heroes or henchmen killed when otherwise out of combat, as they can do massive damage in a hurry.

Enemy priests casting Word of Healing on themselves are quite potent healers. It helps immensely to daze them, after which they die pretty quickly. Be aware that the enemy rangers have Throw Dirt, which causes blindness and can make most skills that cause dazed miss if not removed.

If you wish to do the bonus, you must rush into the third arena quickly to save the king. If you get there immediately, mobs will attack you and mostly leave the king alone, but if you dawdle, they can focus fire on the king and kill him pretty quickly.

Josso Essher healing his associated priest can also be a problem. Locking a mesmer hero with several interrupts onto the boss while the rest of the group kills the enemy priest can prevent the boss from causing too much trouble. A player mesmer is unlikely to have the necessary reflexes to interrupt the monk boss's heals.

One of the groups associated with Custodian Phebus at E5 won't come out of the small room with the boss and priest on its own. Casting a line of sight ignoring spell on one of the mobs through the wall will get it to come. Pull the group well out of the room, or the enemy priest will step up to heal it. The group has two Forgotten Arcanists that can cause major trouble for your group with Earthquake if you try to ignore them to kill the enemy priest.

NPCs

 * Ghost
 * /20 Ghostly Hero
 * 24 King Khimaar

Monsters

 * Devourer
 * 20 Rockshot Devourer
 * Enchanted
 * 20 Enchanted Sword
 * 20 Forgotten Champion
 * 20 Enchanted Bow
 * 20 Forgotten Avenger
 * Forgotten
 * 20 Enemy Priest
 * 20 Forgotten Sage
 * 20 Forgotten Cursebearer
 * 20 Forgotten Illusionist
 * 20 Forgotten Arcanist
 * Giant
 * 22 Sand Giant

Bosses - elite skill captures

 * Enchanted
 * 24 Custodian Hulgar - Warrior's Endurance
 * 24 Custodian Phebus - Marksman's Wager
 * Forgotten
 * 24 Josso Essher - Word of Healing
 * 24 Hessper Sasso - Order of the Vampire
 * 24 Goss Aleessh - Mantra of Recovery
 * 24 Issah Sshay - Ether Renewal

Dialogues
Briefing from the Ghostly Hero.

Intermediate cutscene
Ghostly Hero: ''Before you can Ascend and enter the Rift, you must first be cleansed. Lead me safely to the Rune Circle at the end of this test, and I will cast the ritual to burn away your earthly imperfections. Your first challenge will be to defeat a single legion of Forgotten. Your opponents will be resurrected every two minutes unless you destroy the priest who tends their shrine. Once you have defeated your foes, lead me to the door, and I will usher you into the next challenge. The challenges will grow harder as you progress. If you defeat all of the foes along your path, we will claim the Rune Circle, and you will be cleansed. Prove yourselves worthy, and you will be one step closer to gaining entrance to the Rift.''

Ghostly Hero: ''Defeat the enemy priests to stop the other team from resurrecting. Once the enemy team is defeated, we will move on. Quickly! Through this door. We face much harder challenges ahead. This last battle will test us all. May Balthazar grant us strength and courage.''

Bonus objective:

King Khimaar: ''The Forgotten defile the resting place of my people. Have we not suffered enough...? I will never fully rest until the memory of my people is no longer taunted by these filthy creatures...My spirits have been weakened by such blasphemy. I must see the Forgotten removed from this place before I slip away...In a matter of moments, I shall leave this world for good, never to see my people's resting place cleansed...''

Ending cutscene
Ghostly Hero: ''Under the scrutiny of the gods, your souls will be pure, your bodies cleansed. You are ready for the next phase.''

Follow-up

 * Upon completion of the mission players will find themselves in: Augury Rock.
 * If you completed Dunes of Despair and Elona Reach you now must defeat the Doppelganger.