I just play new expansion yesterday after few month breaks. From the battle replay Behemoth look so massive. I love to fiddling with new toy but I'm wonder how big this gargantuan ship is?

Is it bigger than Snoke Supremacy Mega-class Star Dreadnought or rival Death Star size?

In lore terms, it should be properly massive, rivaling or being bigger than Vodyani Arks (because of an even older, more powerful technology).

In gameplay terms, it has to fit into the battle arena, which is roughly 4km*4km, so the model translates to about 1.5km, maybe 2.

Thanks to the answer, I imagine Citadel will be planetary size as it is able to shield the whole system.
Even the OBLITERATOR can literally obliterate system, it is like the power of god. 

Lucky we don't have the ability to create a planet yet.

Basically the Citadel is a dismantled Behemoth, its parts stripped away to generate the protection field of the Citadel.

I'd imagine that glowing orb in the middle is its power source isn't it?

Thanks Frogsquadron, can't wait to get home and continue my yesterday gameplay.

I believe it is, as you can see from the Hissho Intro:

A citadel shield covers an entire star system as for behemonth size, well its almost twice as big as a vodyani ark, i made a calc on vodyani ark size and i got the following.

Look at this!! now that looks like a cruiser we know cruisers are 500 meters long so doing some pixel scalling with the smallest one which lookes like the closest the ark would be 856 pixels long while the cruiser/bship would be 40 pixels long assuming is a cruiser you get a total lenght of 10.7 km and 21.4km for a b ship impressive!!

so a lenght from 10.7 km to 21.4 km a cube with a length of 21.4 km would have a volume of 9261km*3 and a total mass of 7.2e16 kg assuming ironlike density assuming only 1/1000th of the vol is dedicated to the population you could fit 139,393,939,394 Ofc the number is likely even smaller since the thing doesnt have a cubic shape and chances are that most of the volume is dedicated to power generators/shields/guns and other stuff.

So 21.4 km long then the behemonth would be probably 40km long although this is contradicted by the hissho trailer where we see that behemonths are mountain sized so probably 3 - 4 km long ? 

I'd imagine it was more bigger than that in lore perspectives. Something like same scale with Forerunner Installation 00 from Halo universe.

https://www.halopedia.org/Installation_00

Maye they are, maybe behemonths get largers as you upgrade them, at least we know that the citadel shield is large enough to extend over an entire solar system, thats far bigger than anything the forerunners made at least, and the thing can protect from solar system destroying proyectiles which puts it above most forerunner stuff, anyway i dont think there are no official lore figures for ship sizes, except some pictures here and there. 

I like to run my imagination while playing this game and read their stuff. Forerunner have Shield world and I also wish Endless have similar capabilities.

nuyu wrote:

I like to run my imagination while playing this game and read their stuff. Forerunner have Shield world and I also wish Endless have similar capabilities.

I guess thats the good thing they keep some things vague that you can use your imagination to create your own version of the endless universe, you dont have to stick on some static canon which is nice but i also like numbers alot since they give a lot of inmersion i guess its something hard to balance, i like to think that each pop represents 1 billion people by early game and 1 trillion by late or varies according to the empire im playing also while ships are supposed to be 500 - 1,000 m long i like to thing they are a bit larger like 3 or 5 km just because i like it more that way :P , anyways my point is that if you want to think that you are free too and you might be correct, imagination or not at least we know that the endless could build solar ystem sized shields. 

So 21.4 km long then the behemonth would be probably 40km long although this is contradicted by the hissho trailer where we see that behemonths are mountain sized so probably 3 - 4 km long ? 

Only if you consider earth sized mountains!

Olympus Mons, the biggest martian volcano is some 25 km high so your behemoths can be at least that big while staying true to the trailer.