Annoy the Void
“A terrible creature calling itself Buso has made a nearby mineshaft his new home away from the void. Slay the fiend before he can do whatever it is he came from the dark reaches of the outerworld to do.
Buso draws his power from eerie blue flames which erupt from the carcasses of minions summoned from the void and then sacrificed here in this realm. While these flames burn, Buso will be nigh indestructible. Extinguish the fires before attempting to engage him.— In-game description
Annoy the Void is a level 30 guildhest introduced in patch 2.0.
Guide
Buso
In Annoy the Void, you are required to kill a demon boss named Buso.
In the beginning of the fight, there are 3 blue flames in the boss room. The blue flames give Buso a Damage Up buff. Players can interact with the flames to extinguish them and remove this buff from Buso.
Throughout the fight, Buso summons Void Hounds that will attack the party. When the hounds die, they leave behind blue flames. Players should quickly extinguish the flames as the hounds die.
- Kill Void Hounds, interact with blue flames then focus boss and repeat the entire process as Buso spawns more hounds.
Alternatively, ignore the fires entirely and let the healer deal with the increased damage output.
Tank Mechanics
When additional hounds spawn, make sure to grab aggro on these mobs. Too many adds will aggro the healer and make it difficult to keep up healing the tank and party.
DPS Mechanics
Make interacting with the flames and destroying adds a priority instead of burning the boss. If there are too many hounds, it will make it more difficult to focus damage the boss during the overall fight.
Loot
Rewards: 
3,710 experience, 
180 gil