You can just watch the video and follow my steps, but if you want more detailed info on what's going on, read below:
-If you choose Qunari you can achieve even higher damage, but I prefer to play as human.
-First off, get every skill point that increases 'magic' and 'willpower' (both increase 'attack' by 0,5% for mages), the rest depends on your build. You also should choose to do "Champions Of The Just" to get the attribute buffs in the 'Demonic Dogma' side quest. Get the 'cunning' boost in 'Chateau D'onterre'. In the 'Into The Abyss' questline do all side quests (Fears Of Dreamers, etc) to get attribute buffs. After you kill Gurd Harofsen you should also get a buff to most attributes by retrieving the memories. The alpinist 'Runa' in the 'Frostback Basin' also gives a increase to 'magic' if you ask her to include you in her prayers.
-You should find a fine balance between 'critical damage bonus', 'critical chance' and 'attack', I show in the video one of the best ways to achieve that, but if you can find a better setup, please comment.
'Critical damage' is way superior than 'attack', as in its base form, it gives plus 40% damage bonus to your main hand damage (I've tested A LOT, and 'attack' is always inferior, you should only use high 'attack' if you don't have much 'critical chance') The 'Mask Of The Grand Duchess' is required for 15% crit chance. The 'critical damage bonus' cap is at 190%. For this to be effective though, you need at least 40% 'critical chance', the sweet spot is 55%. It's pointless to go above 190% 'critical damage bonus' for any character, so if you can add some more 'attack' you'll keep getting a damage boost.
-Masterworks should be the 'damage boost if not being hit' ones, you can also use the one that increases 7,5% damage per enemy, or if you're crazy enough, the 'berserk' masterworks.
-Also any pact belts should be used to achieve a massive boost to your chosen element, even the regular, non-enhanced ones, increase damage substantially without taking much of your health. Any pact belt is more worth using than the belt that increases crit chance, as the buffs from the belts are over 90% each.
-Lyrium potions boost magic (attack), therefore they also boost damage.
-You can achieve even higher damage if you add a 'Sigil Of The Deepstalker' to your armor and only attack enemies from behind, but that can be incovenient so I only use it on dragons. Also you can get the 190% 'critical damage bonus cap' and yet retain a huge boost to 'attack' if you use the 'Ring Of Doubt' (replacing every form of 'critical chance' with 'attack') and only hitting enemies when going out of stealth as that ensures critical damage. I'm personally not into a stealth playthrough for a mage though, and the 'Ring of Doubt' has an annoying delay sometimes. Also you DPS in the ending will be lower as instead of constantly attacking you're gonna have to wait until you stealth before you attack. You can also increase your damage with some amulets (boosts to magic and willpower) and sigils (increase attack but reduce healing or crit chance) but 'Andraste's Sacrifice' and 'Sigil Of The Great Bear' have way better benefits than damage IMO.
By the end of the video I compare a nearly maxed out Varric to my inquisitor and as you can see the basic attacks of the inquisitor deal more damage than even Varric's basic attacks.
![](https://s2.save4k.ru/pic/TsL1CTXLR4Y/maxresdefault.jpg)