Monsters of the Void Sea: Space Whales for Rogue Trader

“Towards thee I roll, thou all-destroying but unconquering void; to the last I grapple with thee; from hell’s heart I stab at thee; for hate’s sake I spit my last breath at thee.”


What is space without vast, unfathomable creatures borne from the dark between the stars? Spaceship combat in the 40k Rogue Trader RPG is great, but sometimes you want to shake things up with something familiar yet terrifyingly incomprehensible.

Presented here are some rules for using a staple sci-fi monster with a grimdark twist – void whales.

Here be monsters

Void whales, like many other deep space monsters, owe their allure to being unknown. There is precedent for them in the 40k universe, but their lack of faction or battlefield presence mean even the hardcore grognards won’t know what to do when one turns up. What does it even eat?

This makes them fertile ground as a one-off encounter or recurring forces of nature. They don’t need a deep lore or elaborate reproductive cycle to be used in your games. The less you know, the scarier they are. They do have a basic set of needs and desires, and you can use these behaviours to determine how they act.

Void whales consume the emissions from stars, and their primary food source are void creatures that convert solar emissions into energy, like space jellyfish. Anything radiating similar emissions from nuclear fusion, such as a voidship’s plasma drive, is a target for the monster’s gargantuan appetite.

They can translate in and out of the warp with seemingly no effort, and they they can communicate over unknowable distances with low-frequency psychic signals. They can hone this psychic ability into a focussed blast, intended to stun prey at a short distance.

They can be killed (and a whole endeavour could be set around chasing the one that got away!) but they’ll call it a day if their prey gets a bit uppity. They’ll retreat if their ‘hull’ drops to half, sending out distress calls into the sea of souls.

What in the Emperor’s name could it be calling for? Surely this is a fully grown creature? They can’t get any bigger than this… could they?

Void Whales (Juvenile)
10+40+45120152 (parasites)0
MacrobatteryStrengthDamageCrit RatingRangeSpecial
Massive jaws11D10+212Ignores void shields

In addition to a Movement action, a Void Whale can perform one of the following actions once per turn:

  • Surge: Move an additional D5 VU
  • Psychic scream: Every character must make a Willpower test or suffer 1 Fatigue
Neither Beast nor Ship
  • It has no crew, when called upon to perform an action that requires a characteristic test, use a base value of 45
  • Its weapons use the macrobattery rules
  • It cannot be boarded using normal boarding rules
  • It does not suffer critical hits Canny players may try to direct damage at the eyes or propulsion limbs – you can reward a particularly good roll or clever tactic with the Sensors Damaged or Thrusters Damaged critical hit.
  • It has no morale rating or crew population, any damage to these is ignored
  • It is crawling with bizarre parasites, some as large as a shuttle, that protect it from small craft. It counts as having a Turret Rating of 2.

Caravan of the heavens – sample encounter

This encounter can be deployed at any time, but is best used when players are Boldly Going. A warp route through uncharted space requiring a stop-off in an uncharted system, or an emergy translation leaving them stranded in the middle of nowhere.

Dramatically read aloud or summarise anything in speech marks.

[Audio: Ambient spaceship hum combined with a pirate’s lullaby]

“A great man once said “We are tied to the void. When we go back to the stars, whether it is to sail or to watch – we are going back from whence we came.”

You translate back to realspace and the augers squeal in protest as proximity alarms flare up across the ship. Warp shutters remain rolled down and your pict-capts have been totally blinded by what lies beyond the thin metal skin of your vessel.”

[Augers/Detection -20 test:] This system is supposed to be dead and empty, but there is a ring of biomass surrounding the sun, stretching millions of kilometres across the system. You have translated directly into the ring. Radiation and heat readings are safe

Point defense turret crews report ready and macrocannons are loading. Open the shutters?

Divine light

[Audio: Track 2 – Elephant Music – Andromeda. Read the following paragraphs with dramatic effect! Let the music die down and allow them to soak it all in]

“As the shutters begin their slow crawl upwards, a slice of light carves through the crimson gloom of the bridge. Even the photo-tint of the viewports struggle to dampen the intense radiance. 

Light pours in from everywhere – a million light sources eradicating every shadow where you stand. You are bathed in radiance – not the harsh light of a star, but the cool glow of moonlight. Everywhere you look, the infinite blackness of space has been replaced by brilliance.

Then, slowly, as your eyes adjust, you see that you are not alone 

What you thought was endless light is untold billions of marvellous, luminous creatures drifting in the void, circling the sun in a ring of light the scale of which mankind have never seen before – a radiant caravan of the heavens

The spectacle is so awe-inspiring and so humbling – it reminds you of your place in the universe and your absolute divine right to rule it. The pale, cleansing light fills you with a renewed sense of vigour and purpose and that your place in the annals of history is assured. “

You all receive 1 temporary Fate Point that can be used at a time and place of your choosing during your adventures ahead but cannot be burned.

The creatures

[if the players investigate the creatures:]

  • Their bodies appear to be large, gas-filled sacks, about the height of a person, filled with bioluminescent organs that shift around inside them like a lava lamp made of stars.
  • Attached to each sack-like body are dozens of long, dangling tentacles, streaming out behind like the tail of a kite.
  • They do not appear to react at all to your presence, passing harmlessly through the void shields and sailing gracefully past the viewports of your ship

Howls in the deep

[Audio: Whale noises] “You can hear strange noises coming from outside – a deep reverberation in your chest “

[Audio: Guardians of the Galaxy space chase music]


With a triumphant, haunting cry, a titanic creature bursts into realspace, a wave of pure warp energy following in its wake.

Your augers shriek in protest, the great void creature nearly five times the length of your vessel and moving with incredible grace.

Its sleek body is pockmarked with strange lights and lashed with deep scars, and it propels itself through the void on massive pinions.

Through the lights it reels with drunk delight, swallowing millions of the luminous swarm by the mouthful. As its prey dribbles from its maw it lets out another fearsome psychic wail and banks through the swarm to bear down on your hapless vessel, its terrible vantablack jaws open wide.”

Encounter special rules

Your navigator estimates it will be 3 hours (6 Strategic turns) to complete the warp jump calculations to leave the system. This can be sped up or slowed down to add dramatic tension!

The presence of the swarm does not hinder the ship but plays havoc with the instruments, imposing a -20 to any Detection tests.

If the creature is reduced to half health it calls off the attack, sending high pitched squeals into the void. Something terrifying responds. It’s probably best to leave before we find out what…

Making a monster

I cover how I made this beautiful lad out of an old dinosaur and some tyranid bits in a previous article, Meanwhile on the bench: Void Whale.