This is extremely easy as a prot paladin.
- Pick Holy Avenger.
- Pop ALL cooldowns 10 seconds into the fight.
- Survive with AD, gain ridiculous amounts of vengeance.
- Proceed to destroy the boss.
- Rage at no mount, again.
I misclicked the stopwatch and didn't use SotR in time, which would've given me 4x the vengeance, making it that much shorter. I'll fix it tomorrow, hopefully.