Edit: Sorry - should be 'heel' instead of 'heal'

My PCs have tangled with Alduin as part of the main quest several time. They were only victorious about half the time and those were dear victories that were won at high level with powerful weapons. I'd asked the forums how quickly players have finished the main quest (without mods or console commands) and there were many who said they did it as early as level 10. So what gives?

What gives? Do all dragons have a similar weakness? I tried this approach with a different dragon and it wasn't really any different from other destruction spells. How did you quickly and easily defeat Alduin and can you use the same strategy against other dragons?

Well, if you're dual casting that spell and have Impact, you're probably stunlocking him.

Marked For Death and Dragonrend tend combined with dual Imperial/Blades/Dragonbone Swords (whatever I feel like at the time), tend to finish the job pretty quickly after that.

I've only faced him once. My character had capped magic resistance (85%) and high health. He went down easy like all dragons when so equipped. Took way to much challenge out of it for me.

Simple. Level 10 players face an easier version of Alduin.

Right, I saw the wikia info - but his base health is still 2250(ish)? Of course, if you play at a less difficult setting, that's probably not too hard to overcome. As I understand it, my spells do 1/2 as much damage and his attacks do double damage at Master level.

I was actually dual casting him with Incinerate and Thunderbolt without 1/10th the success (think 40 minutes in real time with tons of potions).

Marked for Death and Dragonrend are a good idea, I'll try to remember that for next time.

The first time I fought him was level.. 7, I think. Or maybe it was 14. I don't remember. But he was pretty difficult; manageable, though. It was just a hectic DPS race, for me. Focus on dealing as much damage as fast as I can, while also healing myself constantly.