The Beast is basically described as a 10m high Ork warboss, first thought to be a statue of some kind.
It has cables connected to it and is covered with armor plates.

A 10m warboss would be at least twice as tall as Ghaz (more like 3 times), and there is basically nothing that big in the Orks or Orruks range, and that is not a machine.
We are basically talking about something as tall as a Deff Dread or an Armiger. Roughly.

So I started to look at the whole range of monsters from AoS and 40k to find out which model could be a good starting point for a Beast.

Here is my selection:
- Bloodthirster/Skarbrand (remove the wings, remove symbols of Khorne, add orkishness)
- Aleguzzler Gargant (not very muscular but he's tall and is not covered by symbols which makes it easy to add orkishness)
- Scyla Anfingrimm (not sure about its size)
- Boneripper (my favorite so far: it has all the mechanical bits in his back, some armor plates already ... the issue is that its body is made for 4 arms so it would need to be well covered in armor plate after sawing the 2 extra arms)
- Daemon Prince (remove the wings & symbols of chaos ... add orkishness)

Which one do you think is the most promising?
Any other suggestion?
Maybe some model outside the GW range?

For the armor plates, I'll use my bitz box I guess.

Also, I'll need some big Ork head. I have a couple from Maxmini that are good for Ghaz size but I'm afraid they won't look good on anything 2-3 times as big.
Any suggestion?