Hello Everyone, Since my party was the first to complete the trial without failure I'll be making a guide to hopefully help everyone with their runs in the future.
Firstly when you teleport in you'll be faced with a lot of mobs. These mobs are really important so make sure you kill each and everyone of them. They give :
You should give these items to your guild leader as they need x750 for the new Relics.
There's also a daily quest you can grab from the start there's a quest giver on the right hand side, you'll get Stone's from killing the boss.
When you get to the boss area you need to keep these things in mind.
1. Every time you see the crystals spawn go and kill them instantly, especially the Blue one or your party will wipe.
2. When you see a big AOE on the floor run to one of the smaller orbs located around the area to prevent yourself from being 1 shotted. It's similar mechanics to Robo in Shale Cavern Trial.
Run to these when you see a massive aoe on the floor;
After you kill the crystals you're free to dps the boss as you wish with whatever classes.
Note. You will need 2 healers atleast and a Holy sage.
Demonfire (Demon Tamer Skill) doesn't work on this boss.
The boss is pretty fun and simple to do if people actually listen so have fun.
Credits to Mike for Making this guide ~ (copied and pasted the whole thing)