The Talos Principle: Road to Gehenna is absolutely packed with Easter eggs, referencing everything from Portal to Serious Sam to Harry Potter fanfiction and beyond. Take a journey through the digital realms of robotic enlightenment and discover some strange secrets hidden away in this expansive add-on.
Fans of the original Talos Principle are probably already aware how many Easter eggs Croteam managed to stuff into each nook and cranny. So it should come as no surprise that the references return in Road to Gehenna, and they’re even more obscure, bizarre, and hilarious. Get a taste of what’s been found so far in the sections below.
Road to Gehenna Easter Eggs
Ancient Egyptian Portal Turret
This first Easter egg in Road to Gehenna might be its coolest. Hidden away in one of the World 2 puzzle rooms, sneaky robots can make a very specific jump and check out a genuine Portal turret.
These talkative turrets were a fixture of Portal and Portal 2, and this is yet another cool addition from Talos Principle’s most obvious first-person puzzling inspiration.
To find it, travel to World 2 and from the spawn point turn right, entering the Bunny Hop puzzle. Complete it like normal, then jump up to the upper platform with the switch.
From this high-point, you’ll want to jump over the walls protecting the red / blue laser projectors on the right (from the entrance) or the left (when attempting the jump) — if you can make this tricky leap, you’ll land next to some stone steps.
Jump onto the steps, and you’ll come face-to-face with this memorable prop from Portal.
Serious Sam: The Text Encounter
Serious Sam gets retro in a text-only adventure with one cool secret file available in World 2. From the starting point, travel left until you find a very conspicuous ruin with multiple ramps and platforms. It looks like you can climb it — because you totally can.
Reach the tallest pillar. On top of it, you’ll find a blue secret file; it takes another jump just to see the top of the pillar. It’s a blue floppy disc with ‘Top Secret’ written on it.
Take this secret disc to the terminal at the start of the area to access it. Confirm the upload at the terminal, and you’ll get an option to play Serious Sam: The Text Encounter!
Just like old text-only adventure games, you’ll type in simple commands to solve puzzles. In this case, you’re the Croteam creation Serious Sam, a fast-paced crazy FPS. So, this is a match made in adventure game heaven.
Instead of fighting Sirian Werebulls, Serious Sam does battle with ennui in this dour bit of coding. It’s a long, hilarious joke that goes on for a shockingly long time. If you’re looking to see Sam’s deep depression, this is the Easter egg for you.
Road to Gehenna Easter Eggs
Floating Isle of Bunnies
There’s a floating island in World 4 that’s overrun with fluffy bunnies. Pointless? Maybe, but it exists, so we’re going to tell you how to get there.
As previously stated, travel to World 4 and jump down to the island with the Colliding Beams puzzle. Snake around to the ledge to the right of the entrance. There’s another tiny island across the gap, and it’s completely covered with bunnies.
Zoom in for a better look. Maybe it doesn’t count for anything, maybe it’s just more Croteam weirdness, but this little speck of dirt looks unique enough to deserve a mention.
It’s even possible to reach the island. Use the fan (the same you used to reach the Colliding Beams puzzle) and bunny-hop / skid across the surface to keep your momentum and leap to the isle.
There are bunnies having a tiny tea party and everything. It’s an Easter bunny festival, and you’re invited.
An Irrational Magician
Deep within the World 4 puzzle room Goliath, your robot can find a secret area filled with seven QR Codes painted on the walls of an obscure corner.
Get out your smart phone and start scanning… or we’ll just tell you what these codes say right now. Are you ready?
“Happy happy boom boom swamp swamp swamp!”
So, what does that mean? I’m glad you asked. This phrase is from the infamous fanfiction opus ‘Harry Potter and the Methods of Rationality’ — a bizzare alternate universe take on the story where our hero Harry takes on his enemies with the power of completely inappropriate scientific rationality, sexism, and endless soapboxing.
Additional Source: 
Kevin Thielenhaus is a freelance writer for The Escapist. Find him on Twitter here.