Here are my own stats for the Void-Whale, enjoy.

Void-Whales

Dimensions: 9.8 km long, 4.7 abeam at fins approx.

Mass: 500 megatonnes approx.

Accel. 0.9 gravities max sustainable acceleration.

Speed: 3

Maneuverability: +15

Detection: +25

Hull Integrity: 105

Armour: 19, (23 Prow)

Turret Rating: 1

Void Shields: 1

Weapons: Maw (Strength 2; Damage 2D10+13; Crit Rating 4; Range 0).

Special Rules

Neither Beast Nor Ship: See Void Kraken for details.

I like it, but why does it have Void Shields and a Turret Rating? I would give it neither, and bump the armour up a point or two.

Turret rating is fine, I believe the void keracken has one.

It can represent a huge number of things from schools of tiy void fight that swim near the whale and get in the way to a thick layer of mulisk like creatures that act as a fleshy shield.

The void shield should go. Its got the armour and hull to tank damage and unleasa its heavily tainted by the warp, I can't see how it would have its own shield.

I do think the manuverability is too high, considering the size and the fact its a whale. Not the most nimble creature.

It also needs a specialty. ATM all it can do is a powerful ram. Give it something the players will remember it by.

Sin for instance from FFX spawned little creatures. Roll with that and you have a living carrier that can also make boarding actions.

Fleshy shield standing for turret rating can play double role of void shield imo.

IIRC some void whale once devoured whole ork fleet, so this 9,8 km one should be considered baby-whale, which speciality can be "Call Mama".

That is one whale of a void whale! 10km?

I think the stats are fine, even the void shield. However this thing is "swimming" through the void should create some sorta interference--releasing gas, some sorta static discharge, etc.

The real question is, how much can gelt can I get for a pound of void whale blubber?

Probably less then one gelt wholesale, but with the amount you'll pull off, i'd still be worth it.

Makes me tempted to introduce an area with a large void-whale fishing industry, that uses the oil to fuel everything planetside. Ah, braving the dangers of a dozen whaling vessels trying to take down a whale!

Since there's no sound in space, unless it's convenient and/or dramatic (lasers and explosions, for instance), I almost wish that they had some sort of "harmless" psychic ability where you hear whale songs, like Humpbacks make on Earth. It might also be how they communicate, where sound can't facilitate. I have no idea if the void whale is more of a gentle "happens to live" creature in space, or a Moby ****-like brazen killer, hunting ships for food, like void krakens, and maybe hunting those, too, like sperm whales hunt giant squid.

Since there's no sound in space, unless it's convenient and/or dramatic (lasers and explosions, for instance), I almost wish that they had some sort of "harmless" psychic ability where you hear whale songs, like Humpbacks make on Earth. It might also be how they communicate, where sound can't facilitate. I have no idea if the void whale is more of a gentle "happens to live" creature in space, or a Moby ****-like brazen killer, hunting ships for food, like void krakens, and maybe hunting those, too, like sperm whales hunt giant squid.

That is Perfect, Can I use this in the background I am writing?

Sure, I'm good with it. Have fun.

Limited psychic ability could also explain how migrate get from system to system. They might "Dive" into the warp/real boundary and swim along for a bit before the pop back out 4 or 5 light years away for a "Breath". (Which is functionally similar to how Tau drives work)

I do believe a full grown Void Whale should be 20km long.

I like the idea of it being capable of warp travel, I also like the idea of it having psychic whale songs that affect everyone nearby. You could also scale up some Psyker and Navigator type abilities for ship level combat it could have, like for instance a ranged kenetic attack. The jaw weapon is good but I'd go one step further and give it the ability to grapple a ship it bites if it gets enough degrees of success much like the kraken with additional rules for eating/swallowing the ship.

I'm thinking in order to make it valuable yes go with the blubber being renderable into extremely high energy fuels but in addtion it's skin should contain compounds with warp insulating properties and also rare elements required to build geller fields, and that it's head should contain crystals that can be used to produce psy-weapons and psy-focuses.

To balance this all out though make it far deadlier than what you've currently got, make seeing one turn up into a pants crapping experience where you're not sure what it's going to do or whether trying to kill it is even worth the risk.

I do believe a full grown Void Whale should be 20km long.

I agree, also I say up it's speed to 4 and let it make a 45 degree course change every two void units it travels allowing it to turn up to 90 degrees total each turn without having to make any "piloting" checks.