This guy really DOES scale to MR. Surprisingly so. I removed two maxed Green Overwhelming talismans - substituted with 2 Mystical (no increase in ATK or Magic so I've always ignored them) at level 38 - and his damage INCREASED.
So I'm thinking that means his HP, both his DEF and his MR, and his damage can be maxed with a bunch of Mystical talismans. The kind I've always deleted . Which will also make him a defensive beast
I have three purple talismans on him now which provide the MR but not as many hit points
I wish Green power-up runes weren't so frickin' hard to come by. I'd like to test my theory, and leveling all those Mystical Talismans will take forever. I know there aren't a lot of Viking Eddies out there, but for those who have him please post what's working best for you...