Shout Out / The Talos Principle

• Aside from the famous writer who challenged the Church and tried to update religious philosophy, the acerbic and critical "Milton" in the game may have been inspired by the early electronic game of the same name, which was known for sarcastically insulting its players.
• There are several Portal references:
  • In one level, the moon is very large, and if you look closely, there's a connector pole on it. Shoot a laser at the connector, and the whole moon rotates, revealing the Aperture Science logo. Once the logo is visible, there's a telescope you can use to look closer at it, and you can actually see Wheatley there as well.
  • When you first get access to the hexahedron, there are QR code messages nearby that talk about the odd naming scheme for it, lampooning the Portal naming scheme for its Weighted Companion Cubes.
  • If you jump out of the walls of "Bunny Hop", you can find a turret half buried in the sand.
  • The achievement for first using a hexahedron and its description are "Not a Cube"/"...but let's be honest, it works the same", referencing how it functions almost exactly the same as Portal's cubes.
• One puzzle is called “Don't Cross The Streams!”
• In the desert, you can steal a hexahedron and a connector to reveal a 3D version of the cover art of The Dark Side of the Moon. Using it causes a short music clip resembling the opening of "Shine On You Crazy Diamond" to play.
• There's an axe in level B7 called the CRObar.
• In level A4, there's a literal Easter Egg.
• When exploring the beaches of level A7, you can find a terminal whose screen shows the Blue Screen of Death.
• The design of EL's racks brings to mind IBM's Blue Gene supercomputers.
• One of the messages you can paint on walls (if you've completed the Sigils of Elohim free promotional game) is "These sigil locks come naturally to me. Perhaps I have some Russian in my lineage."
• In area B4, there's a secret area right behind you at the start. When you activate the wall with the secret, it slides down... revealing a big red ENTRY DENIED stamp that may look familiar to anybody who's played or watched Papers, Please. To get ENTRY GRANTED to A̶r̶s̶t̶o̶t̶z̶k̶a̶ the secret, you need to find a green stamp.
• There's a hidden room in level B7 with a number of boxes from various games, including a crate from Serious Sam, a cube from Minecraft, and the companion cube from Portal. Within one of these crates hides a cat you can free, which alters the "Free Will" ending slightly.
• Behind the walls in one of the World C levels is a diamond sword from Minecraft embedded in a rock (which might also refer to the legend of Excalibur). You can use it to cut some vines in the hub to find a hidden QR code that reads "You are not here" (a reference to Antichamber).
• Before entering the puzzle on the tower's fifth floor, there's a QR code that, when scanned, reads "Nulla è reale, tutto è lecito. Requiescat in pace." It's a hint for how to reach the last star: climb out the window, shimmy across some platforms, and walk off a ledge.
• You are an android who can literally dream of electric sheep.
• Congratulations! You have just vanquished an evil serpent-god with your bare hands! Unbelievable, isn't it? (Yeah, right. Dream on.)
• In the DLC puzzle "Goliath", you can find some apparently broken QR codes, that read when using an external QR reader: "Happy, happy, boom, boom, swamp, swamp, swamp".
• When exploring the third hub in the DLC, you may find a Message in a Bottle that it's part of a Scavenger Hunt. Completing it leads to the One Ring underwater.
• Using a hidden telescope in B5, you can see a sunken Statue of Liberty in the distance.
• Even the Messenger worlds contain easter eggs! The one found accessed from hub contains, hidden on a cliff, a cage with a monkey and an infinite symbol inside.
• More than a couple of the secrets/easter eggs reference Serious Sam.
  • World B is reminiscent of the first game's Ancient Egyptian setting.
  • One of the spontaneous holographic replays you witness uses the same sound effect as a Beheaded Kamikaze from the Serious Sam games.
  • And now there's a DLC pack that adds in an option for a Serious Sam skin for your character (as well as shades!), and an option to have Serious Sam's voice replace Elohim. Naturally, unlike Elohim, Sam doesn't take his job seriously at all - he laughs at the player when he dies for the first time, outright encourages the player to climb the tower for a laugh, and even complains about Croteam using Ancient Egypt as a setting again. He pretty much disregards the fourth wall on a regular basis, even to the point where he starts speaking as his own voice actor rather than Sam in one instance.^note Strangely enough, at some points he starts going on strangely philosophical and sometimes outright nihilistic rants, but it might just be him screwing with the player's head for kicks, especially when later on he starts making more encouraging remarks, basically encouraging the player to make their own mark in the real world, no matter how small, because even the smallest marks can have the biggest impacts.
  • The door locked by a red stamp (mentioned above) leads to a hidden cinema where a short Serious Sam film is being projected.
  • A poster is hidden in one of the outer walls of the tower, accesible only by dropping from a window (thankfully, there's no fall damage).
  • A Serious Sam can be found in a cave in the C3 cliffs, frozen in what appears to be carbonite.
  • There are several hidden Gnaar: one can be summoned by reassembling a statue whose pieces are scattered around C1, another one is found on top of the mountains in C2 (viewable using a telescope in "Rapunzel"), another one is hanging on a cliff in "Weathertop" (and says "Fly, you fools!" when falling), and the last one is found in a hidden ice cave in C3 (accesible using the secret jetpack).
  • In World 2 of the Road to Gehenna DLC, there's a floppy disk on top of some pillars. Log into a computer terminal and you can play a text adventure based on Serious Sam, written by 401.
• A hidden area on the rooftop of "Multiply Impossible Ascension" has painted graffiti on it that reads, "Are you enjoying the time of ELOHIM?" The line is a reference to Time of Eve, which tackles robots learning to act more human, and is prominently set in a café whose slogan is "Are you enjoying the Time of Eve?"
• On the secret developer island, there is an epitaph which reads: "I am heavy trigger guy. And this - is my trigger".
• Some text files you find in the terminals have messages encoded in hexadecimal. When decoded, most of them turn out to be references:
  • "Truth was the only daughter of Time", attributed to Leonardo Da Vinci, from the file athena_analysis.html.
  • "The road of excess leads to the palace of wisdom", attributed to William Blake, is in error.log.
  • team_leads.eml contains "through inaction, allow humanity to come to harm", one of the three laws of robotics by Isaac Asimov.
  • progress_rep1.eml has "LIFE UH FINDS A WAY", a line from doctor Ian Malcolm from Jurassic Park.
  • "For, behold, I create new heavens and a new earth: and the former shall not be remembered, nor come into mind", an excerpt from Isaiah 65:17, is found in mail_error.dat.
  • "the unexamined life is not worth living", said by Socrates at the end of his life, is found in beginnings.txt.
  • "Eternity is in love with the productions of time", attributed to William Blake, is hidden in body_and_soul.txt.
  • "No man is liberated from fear who dare not see his place in the world as it is; no man can achieve the greatness of which he is capable until he has allowed himself to see his own littleness", attributed to Bertrand Russell, is found in talos.eml.
  • human_blood.txt quotes the Bible (John 1:14) with the message "And the Word was made flesh".
  • William Blake's "The true method of knowledge is experiment" is in bronstein_brain.txt.
  • apocrypha1.doc hides "the lion & wolf shall cease", from a poem by William Blake.
  • "heaven in hell's despair", part of the poem "The Clod and the Pebble" by William Blake, is in hope.eml.
  • "Energy is Eternal Delight", from the book The Marriage of Heaven and Hell by William Blake, hides in the file contraries.txt.
  • "G1:26" is hidden in archive_IMPORTANT.eml. Probably a reference to Genesis 1:26.
  • "Time is the mercy of Eternity", by William Blake, is in thank_you.eml.
  • "to form the golden armour of science", from the poem The Four Zoas: [9] Night the Ninth by William Blake, hides in apocrypha9.doc.