gw2-eventYou will be required to use your “Special Action” key during this boss fight. You can set this key in options > control options > skills. This key should be accessible at all times.

This fight is quite straight forward and not too complicated. The mechanics are easy to pick up, and shouldn’t take too long to master. However, good group coordination is required to beat Slothasor with ease.

Slubling Run

At the very start of this fight, you will need to make your way through a passage to the main boss area. This area consists of two types of Slubling. The general ones, and Evolved ones. This is a short tutorial giving you access to mob mechanics before the main fight.

I will go into further detail in the Slubling section below.

General Mechanics

There are several mechanics which will make or break this fight. This fight is simple, but there are a few things you need to know in order to succeed.


Throughout the fight someone will be fixated. This changes randomly between the players in the squad, so there is no need for a tank in this fight. Fixated players will need to pull the boss around the area to safe points where the rest of the group can attack.

This mechanic is the most prominent, so everyone should understand how to deal with it. If you’re fixated, there will be a purple glowing marker above your head. Everyone will also see an announcement on the screen which mentions who has the fixation.

Your goal is to move the boss around the area safely and efficiently.


Much like the fixation, poison will be randomly applied to members of your group. Once this happens, there will be a green skull mark above the players head. If you’re marked, your goal is to get out and away from the group as fast as possible. You will need to take the poison to the edge of the area and drop it as far away as possible, preferably behind the group and next to a wall.

Once the poison has been dropped, it will slowly grow form a small circle, to a much larger one. If dropped in the wrong place, this will fill the area, resulting in possible death of your group.

This requires you to have your special action key bound to an accessible location. By default it is “-“. It doesn’t matter what you have this bound to, just as long as you can access it with ease.

Poisoned Ground

As you enter the area you will see that the whole floor is glowing a bright green. The whole area is covered in a poison which needs to be cleared. Standing in the poison will cause damage to yourself, and whichever group members may be standing in it. Several players will need to eat a mushroom and clear a path for the group.

This is further detailed in the section below.

Imbued Mushrooms (Slubling Form)

During the fight, you will need to designate several players who will eat mushrooms around the area. This requires a player to run up to the imbued mushroom, interact, then proceed to clear the smaller mushrooms around the area with skill 1. This allows your group to move around the area and stay safe. There are several ways to deal with this, most groups assign 4 people, and have several back ups in case someone has poison to drop.

There are two main paths which your group might use, inside path, or outside path. This should be decided before you start eating mushrooms to reduce confusion. This is all dependent on how your group wants to deal with the spawning Slubling mobs.

After becoming a Slubling and eating mushrooms, you will gain a debuff (Nauseated). This will stop you from eating further imbued mushrooms for 4 minutes.

Becoming a Slubing has it’s purpose, but it also has it’s dangers. If your group isn’t paying attention, they may kill you by accident. Once transformed you become hostile to your group. So keep in mind where your group is, and what they’re doing before consuming the mushroom.

Slubling Mobs

Throughout the fight there will be an infinite amount of Slublings spawning in the middle of the area. You need to deal with these enemies throughout the fight. Ignoring them will just result in death due to how many can spawn. The most common way to deal with these enemies is to reflect and pull them together on top of the boss while working your way around the room.

As the fight progresses, Evolved slublings will spawn instead. Even though killing the boss is a priority, these enemies can make or break a fight so you can’t ignore them.

Keep in mind that Slublings may apply mass amounts of conditions, but they also corrupt boons, making this fight more tedious than it needs to be.

Slothasor Boss

Out of all the raid bosses, this one is one of the most simple, he has very little attacks, with big telegraphed call signs for each attack.

The following attacks happen somewhat randomly, but some happen at set points. The party should always be behind Slothasor, and only the fixated should be in front. If the group is caught by one of his devastating attacks, it can cause a wipe.


This will be the first attack Slothasor performs on the group as you start the fight. He will slam his arms against the ground much like Gorseval, but instead orange AoE circles will appear under each player. Three circles will pulse 3 times, then knock down whoever is standing in them.

Grouping up is a good way to avoid how many of these circles fill the area. There’s only one way to avoid this attack, and that is to dodge. The most common way to avoid this attack is to dodge on the count of 2. As soon as you see the AoE light up two times, then dodge away.

This happens to be one of the more frustrating attacks which hits most players because even though AoE’s may disappear from the area, it’s still possible to be hit by their effects if you run back over the area too quickly. It’s also possible to dodge into other player’s AoE marks which gives the same result.


Every so often Slothasor will stand up tall, then lean forward to breath a fiery breath towards whoever is fixated. This is fairly easy to avoid due to how long the wind up animation is. But be careful, it’s very easy to get caught up in the fire which will instantly down or even kill some classes.


While moving the boss around, he will swing his arms at the fixated. This attack deals very little damage, but it’s best to avoid it at all costs if you’re prone to easy death.

Spore Release

At 50% and 25% health, Slothasor will start to perform a new move set where he will shake. As he does this attack the area will fill with poison spores which will instantly down a player who is hit by multiple. The best way to avoid this is to save dodges for this attack. There’s very little reason to dodge in this fight, so you should always have stamina to avoid this attack.


With every 20% of the boss’s health depleted, he will fall into a deep sleep. When this happens your group will need to use crowd control skills such as stuns, chills, knockbacks, pulls and so on. This will destroy the Defiance Bar, resulting in Slothasor waking up.

After every Defiance Bar mechanic, Slothasor will stand up and fear everyone in the vicinity. There are two ways to avoid this, one is to dodge at the right moment. The other is to use a stun break.

Most commonly “Gale Song” would be used here by Tempests in your group.  This is a very effective way of protecting your group from being feared. Guardians using “Stand Your Ground!” is also very effective.

If anyone happens to not stun break or avoid this attack they will be feared off into the poison field and die.