Imperial Fortress Walls
The biggest Emprahfucking building set piece ever produced by GeeDubs. The Imperial Fortress Walls is a hilariously ECKS BAWKS HUEG fortification made by Forgeworld back in 2013. Originally on sale for 800 GBP (Or a 1029.58 Murican Dollars), the sheer size of this monstrosity could easily be a war table in of itself.
Encompassing an entire 4 x 6 table, it cannot be reinstated that this resin kit is ECKS BAWKS HUEG. Once fully assembled, a Baneblade can fit within the walls and front gate of the Imperial Fortress. Adorned with Gothic buttresses and defence cannons, this Fortress can be defended with ease.
Crunch
As aforementioned before, this thing is big enough to drive a Baneblade through and twice as expensive, this is the big daddy of fortifications. With T10, W40 and a 2+Sv, you'll need two Baneblades just to take it down.
It doesn't have any major weapons for all the flare, but it can take eight heavy bolters, lascannons, or long-barreled autocannons and, praise the Emperor, has BS4+ to go with them. You can also put 60+ infantry on top of it, giving them 4++. Unfortunately, they are rare to the point that the existence of models can be questioned. If you're Chaos, you could substitute a Helfort, but they're increasingly rare, as well.