Okay, that last part is arguable, but he's certainly the most formidible according to the statistics lovingly kept by Tibs.
I specifically chose Norman out of the six we had randomly selected this game because I am convinced that passing his personal story might well be the key to victory against an AO we could not otherwise defeat in final battle. When we drew Atlach-Nacha I had to supress a groan; I knew we were never going to defeat him in combat whether Norman found his weakness or not.
Our initial draw for starting items was very low on weapons, but Norman did wind up with the Walking the Ley Lines mission. Now usually we win against Atlach-Nacha by sealing, but we had triumphed by completing this mission against him once before, and our last couple of attempts to seal the Spider God away had been dismal failures. And Norman did have his starting Find Gate spell, and we also had Jacqueline and Marie's character abilities. All and in all, it was about as perfect circumstances for attemping the mission as we were going to get. My teammates were up giving it a shot, so we went for it!
Our second Mythos card was Tempest, and because of the "No Mystic Environments" rule we kept Tempest the whole game. Needless to say, it was a godsend! One of the most annoying things about playing against Atlach-Nacha is the way flyers move every turn, but with Tempest they were killed as soon as they reached the sky. The +1 speed was also a big help to max three speed Norman.
The whole game was a nailbiter, with us frantically trying to complete the mission as Atlach-Nacha's doom track seemed to climb every turn. Marie used her Witch Blood twice and it barely seemed to slow him down. If we hadn't sealed the Witch House and Gardener's Place he would have had us; as it was Jacqueline still has to use her Precognition twice. When Norman sacrificed the -4 Ry'leh/Abyss gate at Unvisited Isle to complete the mission the Doom Track stood at twelve and we had eight gates open.
Now our games often come down to the last turn or two. I enjoy a close game even when it goes against me, but this is a win I'm especially going to savor, and I wanted to share the story with my fellow Arkham afficionados.
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. All random stuff, hell, getting Allies from encounters with the decks at 30+ cards isn't easy-peasy-lemon-squeezy. Not to mention actually drawing the darn Mission in the first place, it's just 1 card. As far as challenges and difficulty goes, it's really up there.
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