Trespasser--Final fight

I've usually been maxed out on levels by Trespasser but it still should be possible for you. Who have you got with you? I generally had Cassandra, my archer assassin Inquisitor, Dorian and Vivienne and had no trouble. I've also done the battle with Cole replacing Vivienne as my Inquisitor filled the Knight Enchanter role. Grab potions on the way in so that your allocation is maxed out. Remember to use your special ability as much as possible. It will help knock out the summoned creatures as well as damaging him. (In fact you are obliged to use it frequently or it will overload anyway). Then pay attention for when your companions actually tell you to use it to finish him off.

(If all else fails, drop the difficulty level - unless of course you are already on easy)

Why would you drop Sera? Thousand Cuts should take the boss down to 50% health, unless you've really fallen behind on crafting.

If you drop anyone, it should be Vivienne. Unless you have her mainly on support with Revival and Resurgence? You certainly don't want her closing to melee range. No one should get close to the boss except you, and then you only to hit him with a Meltdown blast.

What kind of mage is your Inquisitor? I can help you with your ability loadout if I know what the spec is.

In general, because of the boss's AoE attacks, you want ranged fighters. You could go 100% ranged with no tank, that works. But if you have a tank, Cass is the best, since her Wrath/Purge is extremely effective against the demons that the boss summons.

Cass should be set to spam Horn of Valor/Fortifying Blast as Preferred in AI. That keeps everyone in guard on hit. 

You should also have maximally upgraded regen health potions on everyone. That has an AoE healing effect that keeps everyone healthy.

Everyone who can use magic attacks should have electric (Storm) and ice (Winter) attacks. The boss is vulnerable to electricity attacks and Winter works for everything else except for Despair demons. It doesn't hurt to have Fire Mine, of course, but electricity should be the priority.

Don't get near the boss until your Mark is at least 2 bars charged. If he sucks you in with one of his grab attacks, that's a great time to let loose with a Meltdown blast.

BTW, probably should have asked this in the tactics sub: bsn.boards.net/board/17/dragon-age-inquisition-mechanics-tactics

It's fine to continue here for this thread, but for next time.

Thanks for the help. I'll try to answer your questions as best I can. First of all I did some of my characterizing leveling wrong. I tended to get everything in a specialization and then move on to the next. That is everything in fire then winter etc. I did mix specializations up somewhat so that Viv is my winter master etc.

My mage is a Rift mage. Sara is my archer, and Cole is my assassin. Iron Bull is gone as I didn't save his men. As for the automated attacks I just let the default settings manage that. Pretty pitiful? I am really pretty much a duffer.

As for health I have the 12 health and 5 regeneration.

I'll have to remember that if I ever play this again. I haven't done anything with potions and anyway at this point in the game I can't go back to Skyholt or even back to the Winter Palace. At least I don't think I can. I could start over from the that point I guess if the Winter Palace has the ingredients, but I don't have anyone trained to make potions etc. But you are right about the quick and dirty solution.

I cheesed the final boss in the Deep Roads expansion and I don't feel guilty at all.

As you see, my chooses also not because of tactics, rather because of fun, or because the Inquisitor found the indirigents. I really hate this system: you can learn the skill, because you can find 5 kitten tails and 3 bat teeths... the whole game about gathering... I can lose my patience too quickly.