Originally Posted by Yendor
Yes, with items he HAS armor, yet he HIMSELF has low armor my friend ;p
Just like doom has low armor, despite the fact that dooms usually build AC or shivas.
The difference is, +armor items are Lycan's core, he will get them asap (Basi or RoP as usual starting item for example), Doom does not.
Therefore, you can easily harass Doom in lane, but not Lycan (aside from the fact that he jungles).
You can't really list armor as a weakness of Lycan.