You’re cruising through the void, minding your own business, when a science ship pings a black hole. Suddenly, you get a message. It’s cryptic. It’s creepy. It says "GRAVITY IS DESIRE" and "TIME IS SIGHT."
Welcome to the Horizon Signal. Honestly, it's the weirdest, most iconic event chain in Stellaris. It’s been around for years, written by Alexis Kennedy (the mind behind Sunless Sea), and it still manages to freak out new players while making veterans salivate for that sweet, sweet Tomb World habitability.
If you've played long enough, you know the Worm. But the game has changed a lot since the early days. Paradox updated the spawn rates and the way the event triggers, so if you’re trying to find it in 2026, the old "patrol your ships in and out of a black hole" trick doesn't work anymore.
What the Horizon Signal Actually Is
Basically, it’s a Lovecraftian love story. An entity from outside time, the "Worm-in-Waiting," has fallen in love with your species. Not in a "let's grab coffee" way, but in a "let me fold your reality into a pretzel so we can be together forever" way.
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It is a massive, multi-stage event chain. You’ll deal with disappearing scientists, recursive loops, and strange temples. It’s long. It’s expensive in terms of research time. But the payoff? It can fundamentally rewrite what your empire is.
How do you actually get it to start?
Back in the day, you could force this event. You’d just set a science ship to move back and forth into a black hole system until the 1% trigger rolled in your favor. Paradox eventually caught on and killed that.
Now, the game rolls for the Horizon Signal at the very start, during galaxy generation. There is roughly a 20% chance (up from 5% in older versions) that a specific black hole in the galaxy is "flagged" for the event. If you enter that specific system with a staffed science ship, it triggers. If no black hole in your galaxy got the flag? You're out of luck for that run.
Also, if you're playing a Gestalt Consciousness (Hive Minds or Machines), you're mostly locked out. The Worm wants individuals. It wants souls it can talk to.
The Major Beats: From Nightmares to Messengers
Once the signal starts, things get weird fast. You’ll have a scientist go missing. Then they come back, but they aren’t really "them" anymore.
One of the coolest parts is the Messenger event. You find a pod. Inside is a creature that looks like a mutated version of your own species. You’re given a choice: embrace the DNA or trash it. If you embrace it, your entire species gets a retroviral "upgrade." Usually, this gives you the Intelligent trait but might make your people look a bit... different.
Then there’s the Loop Temple. You’ll find buildings on your planets that shouldn't be there. They’ve always been there. They were built yesterday. Both are true. Dealing with these gives you a choice between embrace and rejection, shifting your empire’s ethics toward Militarism or Pacifism depending on your path.
The Omega Alignment
This is the point of no return. To finish the chain, you have to build the Omega Alignment building on your capital. It requires a massive amount of physics research. Once it’s done, you craft the Omega Seed.
This is where you decide the fate of your galaxy. You can summon the Worm to your home system.
If you say yes to the Worm’s embrace:
- Every solid planet in your home system (including moons and even gas giants, sometimes) turns into a Tomb World.
- Your species gains the Natural Physicists and Repugnant traits.
- More importantly, you get Tomb World Habitability.
Think about that. If you have a system with 10 planets/moons, they all just became habitable. Your economy will skyrocket. It’s arguably the strongest single-system buff in the game.
Why Some Players Hate the Worm
Not everyone wants to be a mutant living on a radioactive rock. If you refuse the Worm at the end, it doesn't take rejection well. It spawns as a massive boss—essentially a unique Leviathan—right in your home system.
It’s a tough fight. If your fleet isn't ready, the Worm will chew through your starbase and wipe your capital. But if you kill it, you get a massive chunk of research and the satisfaction of knowing you didn't let a time-traveling parasite date your entire species.
Strategy Tips for 2026
If you’re lucky enough to trigger the Horizon Signal, keep these things in mind:
- Move your Capital: Before you finish the Omega Alignment, you can move your capital to a system with the most planets. Since the Worm transforms everything in the capital system, moving to a system with 12 barren rocks will give you 12 new colonies.
- Watch your Leaders: The event chain loves to "eat" your scientists. Don't send your Level 10 legendary genius to investigate the signal unless you're okay with them disappearing into a dimension of pure screaming.
- Check your Ethics: The chain can force ethic shifts. If you’re playing a very specific build (like Fanatic Purifiers), the shifts might mess with your civics.
The Horizon Signal is a reminder of why Stellaris is more than just a spreadsheet in space. It’s a horror story. It’s a tragedy. It’s a massive economic boon.
What to do next
If you're currently in a game and haven't found it yet, send a science ship to every single black hole you can find. Don't just scan them from afar—you have to actually enter the system. If you've already explored the whole galaxy and it hasn't popped, it probably didn't spawn this time. Better luck in the next cycle. After all, what was, will be.
Next Steps for You:
- Check your current galaxy: Look for black holes without Guardians (like the Dimensional Horror). These are your best bet for a trigger.
- Plan your capital: If you suspect the event is coming, scout for a system with the highest number of celestial bodies to maximize the Tomb World transformation.