Seems to me that the Wildlands have gotten no love. The are plagued with terrible bugs.
Off the top of my head:
Pyre of man throws fireballs like a lv 1 champion at stupid targets and when you do kill him the grassland that spawns has glowing molten rocks sticking out of places.
The Imperium, once conquered turns the river into plains while leaving them looking like rivers. Is only a 4/4 and not worth the effort. Has a bunch of weird graphical and placement issues with its walls where they disappear and reappear in fog of war.
The Ruin of Summer seems to be easily killed with autocalc.