Dragon Age Inquisition: Dispel and Spell Purge
I've played a fair amount of Dragon Age Inquisition by now and thought I'd mention a mechanic which I found to be quite subtle. I say subtle because I recently found it, although I have no doubt that skilled players have been using it for a while.
Dispel and Spell Purge
These two abilities are VERY useful, more than you may think in fact. Ordinary uses include the removing of defences such as Barriers and Guard, along with removing debuffs.
Two of the best uses for them are when facing High Dragons and when closing Fade Rifts. All mages have access to the Dispel ability (ifskill points have been invested) while Spell Purge is exclusive to the Templar specialization of the Warrior class.
(Note: Dispel can be targeted in a specific area whilst Spell Purge affects the area around the caster.)
Certain High Dragons, (such as Vinsomer) Have abilities which persistently affect characters. They take the form of rings which plant themselves at the feet of your party members. Both Dispel and Spell Purge can remove these, making the battles far easier.
Both abilities can be exceptionally useful when closing fade rifts. When spawning, demons from the rift emerge from what appear to be green pools; targeting these with either Dispel or Spell Purge can remove the demons from the fight before it even begins. I found myself using these abilities for virtually every rift on Nightmare mode.