Deltarune offers plenty of hidden content, NPC encounters, new characters, and Easter eggs to explore. Within the game, there are special items referred to as Eggs. These particular items can be found in concealed locations that require a keen eye, some bit of luck, patience to retrace your steps along with some trial and error. They do not directly impact one's progression in the game but for people who love the series, they are delightful additions that enhance Deltarune's peculiar yet lovable universe.

Chapter 1  

The forest area of Dark World contains an Egg Room which is adjacent to the bell tower and Starwalker fight encounter. This segment of the game unfolds during chapter 1’s second half. Be sure you collect this Egg before tackling the last boss of the chapter since you won’t be able to access it again after that point.

Here’s what to do:

1. Navigate to the room with the bell.
2. Move back and forth repeatedly between the bell room and the Starwalker’s room.
3. There’s roughly a 2% chance on each transition that a hidden Egg Room will spawn, so you may need to try this 20, 30, or even 50 times.

Eventually, you’ll be transported into a hidden chamber featuring a red tree and a cloaked NPC. Approach the figure from behind the tree and interact. You’ll be presented with the option: “He offered you something”. Select Yes to receive the Egg.

After claiming it, be prepared, enemies in previous rooms will have respawned, so keep your party ready for battle as you return.

Chapter 2

The Chapter 2 Egg is hidden just past the humorous traffic lights mini-game. Once you finish dodging vehicles and proceed into the next alleyway, you'll trigger a gag cutscene where Kris is run over by a car (driven by none other than Toby Fox himself). Even the game-over screen gets a laugh, before it too is crushed.

After this sequence, you’ll spawn near a dumpster decorated with graffiti, notably featuring a tree drawing. This is your cue.

To find the Egg Room:

• Walk back and forth between this alley and the city streets.
• Much like in Chapter 1, there’s about a 2% chance of the secret room appearing on each screen transition.

When it finally triggers, you’ll enter a bizarre, dreamlike space with another tree and a familiar NPC from Chapter 1. Walk behind the tree to initiate a new dialogue prompt: “He might be happy to see you.” Choose Yes to claim your second Egg. Declining will leave you empty-handed.

Chapter 3

Chapter 3 presents the most complex journey to an Egg Room so far. This time, you’ll be working your way through the TV World, a surreal game-show realm filled with puzzles and quizzes hosted by the enigmatic Tenna.

Follow these steps:

1. Advance through the TV World and complete Tenna's quizzes.
2. Solving them unlocks a secret path that leads to a block-throwing mini-game by a river.
3. Use Susie to throw a block through bushes and open up the path forward.
4. Reach the Green Room and speak with an NPC who accuses you of cheating.

During this conversation, select the options “Cheater” and then “Nowhere”. You’ll be teleported to an eerie location called Nowhere.

Cross the newly built bridge and press the button at the end to proceed. This leads to an enormous screen guarded by another NPC. Keep talking to him until a wardrobe appears out of nowhere. Open it to receive a Trip Ticket. Take the Trip Ticket and locate the warp door leading to Goulden Sam. Once inside, find the closed dumpster and inspect it to trigger a battle. During this fight, use the ACT menu and press the left arrow key instead of choosing an action. This odd input will teleport you to a secluded place called the Forgotten Isle.

Once there, you’ll encounter a cloaked figure near a tree, yet again. To receive the Egg, you must answer a sequence of dialogue prompts correctly:

• "Will you forget me, too?" → No
• "I ask again, will you forget me?" → No
• "The whole world looked like this. Do you think so?" → Yes
• "Do you understand what I am saying?" → Yes
• "Did you want to meet again?" → Yes
• "Did you remember to write it down?" → Yes

Chapter 4

The fourth Egg is located in a visually stunning hallway within the second sanctuary of Chapter 4. This area is lined with stained-glass windows, surreal monologues, and ultimately ends at a shrine covered in moss.

Here’s how to find the final Egg Room:

1. Progress through the sanctuary hallway until you reach a series of stained-glass windows.
2. Look closely at the shapes at the top of each window. Most appear to have inverted egg shapes, but one has a proper egg-like oval at the top.
3. Walk into this specific window.

As with earlier Eggs, you’ll need to enter and exit repeatedly until the hidden Egg Room finally appears. When it does, you'll find yourself in what resembles a dimly lit hospital lobby.

Head toward the center of the darkened room. After a moment, a mysterious message will appear: "Well, there is a man here. He seems to be pointing at something and nodding."

Move slightly closer to the nearby door to trigger another line: "Well, there is a Canvas here." Followed by: "Will you draw?"

Choosing Yes starts a poetic sequence where Kris paints something. The description ends with the phrase: "An Egg was picked up from a nearby easel."

Keep in mind! If you’ve already acquired the Shadow Mantle, this Egg Room becomes permanently inaccessible, so be sure to grab the Egg beforehand!

What Do the Eggs Do, Exactly?

The Eggs from Deltarune continue to be a significant enigmic aspect of the game. Because they do not boost your stats, aid you in battle, or even remain in your inventory through chapters, they seem designed for players to find them. However, fans assume that there is some form of overarching narrative tied to them which won’t be revealed until the game is fully finished.

They do incite small, quirky interactions in each chapter.

• Chapter 1: If you place the Egg in Asgore’s fridge, the description changes to “There are two Eggs inside.” If you drop the Egg, only one shows.
• Chapter 2: Place the Egg in Sans’ shop basket. Susie quips that Kris has “reverse-stolen” it, and the pile later shows “more eggs than usual.”
• Chapter 3: Leave the Egg on a desk in Berdley’s classroom to trigger a humorous scene.
• Chapter 4: Its use is still unknown,perhaps more will be revealed in later chapters.

Finding every egg hidden throughout Deltarune requires some degree of luck and attention to detail. Despite providing no purpose within the gameplay, these concealed items give players an enriching experience which conveys deepening lore and surreal scenes alongside a lingering feeling of mystery.