When you are in contol of an enemy you can use its buffs and certain spells. For example, in an instance you could control a mob use it spells to heal your party or to attack other mobs.

Undead Priest

Undead Priest

When in PVP its best to Mind Control a Mage they can Dot, massive spell damage, polymorph give intellect buffs ect. It’s also alot of fun to mind control the enemy of Lumber Mill in AB or just let them walk of the Flagspot in EOS .

An little downside is that the cast time is long and the range is quite short, its also unpredictable sometimes its 1 sec and the other’s last for 60 sec. As a Priest in an Instance your main focus is to heal so when your Mind Controlling mobs your not healing your party members so you cuold wipe.

It seems that the spell works longer and better the higher you are in level.

When Priests are in a Neutral towns they can Mind Control and Pain without drawing agro from the guards.
Go to a Neutral Town choose a victim Dot him hen they attack back the guards will attack them!
Priests are able to (Mind Control) and Pain (DoT) in Neutral towns without drawing agro
from the guards. Enter a Neutral town, DoT your victim, and when they attack back they will be attacked by the guards.