Dâr Narbugud/Guide: Îstum

Trash Mobs

After defeating Flâgît, head east back towards the first room in this area and proceed down a ramp to the southeast. At the bottom of the ramp is a group of mobs consisting of:

Beyond this room is a large room with three groups of mobs that include the following:

Some of these mobs have the Aura: Bloodbound buff which transfers damage dealt to the Dark-maw Masters to other nearby allies. This increases the time it takes to defeat the Dark-maw Masters unless they are separated from the rest of their group. The Dark-maw Masters also gain a stacking Incoming/Outgoing Damage buff whenever an ally is defeated nearby.

In the center of room is a Greater Fungal Fumarole. The raid should remain previous room while the tank pulls the closest two groups of mobs to the raid, careful not to aggro the Greater Fungal Fumarole.

Once the groups of mobs are cleared, the raid should enter the large room and engage the Greater Fungal Fumarole, which is similar to Lesser Fungal Fumaroles in that it spawns Fungal Spores, but it also has Gas Chamber, a ground-centered stacking AOE Acid DOT which delivers significant damage at high tiers, so it should be defeated quickly.

After defeating the Greater Fungal Fumarole, the final group of mobs can be cleared.

Preparation

A main tank should be designated to tank Îstum throughout this fight, while an off-tank or heavy armour DPS should be designated to handle Fungal Crawlers in phase 2. Four DPS (preferably ranged) should also be designated to handle Fungal Crawlers in phase 3.

This fight is quite difficult (possibly the most difficult in the entire raid instance) because there is an extremely high amount of raid-wide damage going out almost constantly. Therefore, the raid may want to have three or more healers with plenty of in-Combat revives available. Also because a lot of the damage from the boss is delivered in melee range, having multiple ranged DPS is very helpful.

Everyone in the raid should have Hope Tokens to counteract the bosses' Gloom effect which applies +5 Dread.

Note: This fight can be reset by the entire raid running out of the room.

Boss fight: Phase 1

From start until Îstum reaches 85% / 14.1M Morale

To start the fight the main tank should pick up Îstum and take him to a far corner of the room away from the center (southwest or southeast corner is best). Starting in this phase and for the whole rest of the fight the boss will activate these abilties:

Thunderclap (uninterruptible AOE knock-around followed by a slow)
Combustion (uninterruptible, places ground-centered Poisoned Ground puddles randomly around the room that last for 20s)
Charge followed by Stunned on random raid member
Impending Poison (removable Poison applied to tank that does massive damage on expiration)

DPS should damage Îstum down while staying clear of the center of the room in preparation for phase 2.

Boss fight: Phase 2

From 85% to 40% / 6.6M Morale

"You are too strong! Too many! It is good I am here to stop you!"

Starting in this phase, four Fungal Crawlers will spawn every 60 seconds in the center of the room. The off-tank or heavy armour DPS should stay in the center of the room for this entire phase in order to explode the Crawlers as soon as they spawn ("eating" the damage of the Crawlers to prevent them from affecting others in the raid).

Also starting in this phase Îstum will being activating a very damaging 360° AOE attack called Whirlwind every 35 seconds and continuing to the end of the fight. The attack triggers three times in quick succession and appears as white swords shooting out from his body. If the tank quickly gets out of melee range of Îstum he will cancel the attacks. Whirlwind can also be cancelled by a knockdown (e.g. Exploit Opening or Trip from a Burglar or Smashing Stab from a Guardian).

Boss fight: Phase 3 (burn phase)

From 40% to finish

"What is this? The Mistress ordered me not to fail! Death to all!"

In the final phase, Fungal Crawlers will no longer spawn from the center of the room. Instead every 15 seconds one Fungal Crawler will spawn from each corner of the room (northeast, northwest, southeast, and southwest). At this point the four designated DPS should go to their corners and stay there in order to absorb the damage from their crawlers.

Îstum will add one more ability during this phase: Spore Explosion which occurs every 45 seconds and does massive 360° AOE Acid damage to everyone in melee range. Spore Explosion is preceded by Îstum "beating his chest" for a few seconds while growling and can be interrupted during this with a knockdown.

After a Spore Explosion, Îstum will drop aggro on the tank and randomly attack raid members until taunted back to the main tank with a Force Attack. Because of the massive damage going out to the entire raid during this phase, DPS should burn Îstum as quickly as possible using offensive cooldowns.

Drops

Loot that drops for all characters

Loot that always drops

Greater Elf-stone of Heart (tradeable for DN armour set shoulders)

Loot that has a chance to drop