! My Human Arcane Warrior Warden VERSUS My Elven Knight Enchanter Inquisitor !
(Please note: I skipped DA2 and left Hawke in the Fade, thus 1-on-1.)
Both are epic mages, a human practicing the ancient elven form and an elf using the newer human-modified version. Hard to say which, so it comes down to spells, either the Hero of Ferelden's Crowd Control or the Inquisitor's Barriers + Spirit Sword.
Then my Inquisitor has the "Mark"...but she also has a problem: she doesn't want to use it.
In my Inquisition playthrough, my Knight Enchanter never used that Focus ability beyond escaping Haven. She thought it was too dangerous, too unknown an attack. Sure, she'll use the "Mark" to close Rifts as there's no other way, but that's about it.
She doesn't send everyone into the Fade (i.e. the Elder One) NOT because it's too hard...but because it's too easy. She's afraid of the slippery slope that road leads to. Thus, the fight won't be determined by magic...it's determined by how far each side will go.
The Hero was trained to win at any cost, as is necessary in a Blight. My Inquisitor wants to merely bring order, thus holds herself back. The victor in a straight-up 1-on-1 fight: the Hero of Ferelden.
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However...even in this hypothetical, the above is an academic argument. Should these 2 ever meet in battle, they'll have back-up. Both have too many allies and friends who wouldn't let them go to war alone. Thus, I must consider their supporters:
The Hero of Ferelden's Forces:
The Ferelden Army - King Alistair and Queen Anora owes him their thrones, the whole country their country.
The Dwarves - King Bhelen owes him his throne, plus the Hero fought for them in Orzamar, earning their loyalty.
Morrigan - she still loves him, and will bring knowledge of the Inquisition and the Well of Sorrows...a huge plus.
- VERSUS -
The Inquisitor's Forces:
The Inquisition Army - IIRC most of whom are Fereldens, so this might be weakened due to desertion and morale issues.
The Friends of Red Jenny - a very small force, but can be very disruptive of Ferelden's war efforts through sabotage.
The Orleisian Army - Empress Celene owes her life to him, as does her lover, plus all the nobles favour the Inquisitor.
The Chantry - Divine Cassandra is not only loyal to the Inquisitor, but also a great warrior who'll lead an Exalted March.
The Tevinter Chantry - the Dark Divine acknowledges the Inquisitor as the Herald due to past favours, Tevinter may ally.
Forces Not Participating Due To Other Reasons IMHO: Leliana, the Mages, the Grey Wardens, the Dalish Elves, the Qunari, other Empires. Even though these groups have some relation to the 2 protagonists, their loyalties may be torn or not great enough to throw their people into this fight (like if they're too busy trying to rebuilt, in the midst or re-organization, etc.
Even without analyzing the powers of both sides, I think the Inquisitor will win by sheer superiority of numbers.
This was fun, lol, great topic.