My English isn't perfect, I'm sorry
Since there are several player who have problems with the dungeon and sections between the bosses,
I write a little guide with most important infos.
Up to the first boss are only small mob groups, there shouldn't be any problem.
The totems here and before the 2nd boss buff the whole group with +15% ATK tho,
but they spawn constantly new adds which can be quite annoying.
1st Boss: Desert Worm King
The first boss itself isn't such a problem.
The boss spawns some AOE (Area of effect) circles that can stun you for a few seconds, just try to dodge it.
After a short while spawns a "Fire Instrument", that spawns additional AOEs which deals pretty much damage.
As long as the Fire Instrument is alive, you are only able to deal 50% to the Boss, so kill the Instrument ASAP.
You can skip the whole Fire Instrument phase by freezing (Canoneer, Occultist) and killing the boss.
I can't really explain this section with words how exactly you can avoid the tornados.
It would be the best to watch YouTube videos about it. There are a bunch of helpful videos.
Here are a few examples:
Just try, practice creates masters!
2nd Boss: Magic Desert
Another boss that shouldn't be a problem.
When the boss HP hits ~90-85%, 2 Fire Guardian Spirits will spawn which buffs the boss with additional damage.
If you destroy the Spirits, the boss will get stunned.
There's nothing more to say about that.
Lei Shishi / Mob Section:
When you run through the portal behind the 2nd Boss, you will get to a platform with 10 Lei Shishi spawns.
The AOEs by the totem in the middle deal pretty much damage, so avoid it as far as possible.
Now the important part:
You must kill all 10 Lei Shishi within 10 seconds.
The timer starts after the first mob will get hit.
Try to use classes that can attack whole areas,
for example Mage, Berserker with right talents, Swordmaster and so on
If you are too slow, more Lei Shishis will spawn.
Just let them all spawn, pull them together and try it again.
3rd Boss: Desert Dwelling Dragon
The endboss of the dungeon, that can be quite annoying.
When the boss HP hits ~90% HP, 2 Burning Spirits (they look like warlocks) will spawn.
They buff the boss with additional Crit DMG and lower your Crit rate.
When the boss HP hits ~80% HP, 2 Fulminations (they look like lions) will spawn.
They buff the boss with additional Evasion.
So kill the lions ASAP, otherwise you won't really be able to hit the boss at all.
You can skip both add phases by freezing (Canoneer, Occultist) and killing the Boss.
If you still have questions, message me here or in Discord.
Good luck and have fun!