Gilles is the zone boss of Golden Plains. I have not included every detail. This is information I find important when fighting Gilles.
Weakness: Slash, Strike, Ice
If you attack Gilles with this debuff, you heal him. Luckily, this debuff is removable. Healers can use prevention/purifying wind/etc.; knight can use fearless to remove it.
This is a 50-foot aoe that turns everyone into a bug. If you are already a good distance from Gilles (healer/ranged damage dealer), you can run when you see Gilles dancing with fire around him, then run back and continue. If you are tanking, you can't run out of the aoe in time, so you will turn into a bug.
It doesn't matter if you have 999999999999999 hp. If Gilles successfully damages you with Bite when you are in bug form, you will die. As a tank, when in bug form, get ready to run out of the aoe so you don't instantly die. In the following video, I am using movespeed equips.