Intellect: Raw damage increase on everything.
Haste: Increases cast and tick speed.
Mastery (Mastery: Potent Afflictions): Increases damage done of your DoTs.
Versatility: A weak damage multiplier and damage reduction.
The best way to calculate stat priorities for your character is to "sim" your characterFind out how to sim
Troll > Goblin > Nightborne > Blood Elf > Undead > Orc > Vulpera
Human > Void Elf > Gnome > Dwarf > Worgen > Mechagnome > Dark Iron Dwarf
At the time of writing this guide, you should still use BFA big int gems. If this isn’t possible or has been reduced in value, you should use Haste gems.