In real life, animals' eggs are usually inconspicuous colors like white, grey, and brown, likely because colorful eggs would draw the eyes of hungry predators looking for an easy meal.
Fictional creatures have no such need to hide, and often lay eggs with shells that are not only brightly colored, but match the color and pattern of the creature inside, sometimes down to fur and scales. In a visual medium, this helps the audience guess what might be inside the egg, if it hasn't been established already.
Dragons seem to be particularly prone to this trope. Some reasons are that they're entirely fictional animals, egg-laying reptiles, and are often brightly colored themselves.
Related to Color-Coded for Your Convenience and Amazing Technicolor Wildlife. Sometimes related to Egg MacGuffin, Whale Egg, and Egg-Laying Male. A common feature of Mons series and animal-themed Breeding Sims, and related to Creature-Breeding Mechanic by extension.
- Pokémon Adventures: Gold's egg, laid by Red's Pika and Yellow's Chuchu, has a jagged black design on the bottom that matches Pibu's fur collar.
- Pokémon: The Series: The shells of Pokémon eggs look like the Pokémon they will eventually hatch into; for example, Brock's pink and white Happiny hatched from a pink egg with a white stripe around its midsection. But starting from Pokémon Journeys, this trope is averted when Ash receives an egg that resembles the 10-km egg from Pokémon GO, being plain white with light blue spots and bearing no resemblance to the Riolu that hatches from it. A good thing too, because patterning the eggs after the Pokémon in them made the characters seem oblivious for acting like what would hatch is a mystery.
- Trolls: World Tour: A Troll egg usually shares one physical trait with the baby Troll it hatches, represented either in the shell or occasional hair.
- A Song of Ice and Fire: In the first book, A Game of Thrones, Daenerys receives three dragon eggs as a wedding gift from Illyrio, one cream and streaked with gold, the second deep green with bronze flecks, and the third pure black with scarlet ripples and swirls. They hatch into the cream-and-gold dragon Viserion, the green-and-bronze dragon Rhaegal, and the black-and-red dragon Drogon.
- Dragonriders of Pern: Gold dragon eggs are golden-colored. (Other dragons all have mottled eggs that don't indicate the dragon's color.)
- Wings of Fire: Each kind of dragon has a differently-coloured egg. A minor plot point is that MudWings occasionally lay blood-red eggs, which hatch into fireproof dragons.
- Digimon: Digi-Eggs are sometimes given a themed pattern based around the baby Digimon inside. Other times, however, the egg will either have no actual theme or just be a solid color with no pattern at all.
- Billy Hatcher and the Giant Egg: The player can obtain eggs colored like the various animals they hatch into.
- Dragon Cave: Dragon and drake eggs are almost always the same colors as their eggs, e.g. Deep Seas are dark blue with raised patches of scales, as are their eggs; Rift Wyrms are purple yellow and have purple and yellow eggs to match; etc. Much of the game revolves around raising them from eggs to adulthood, so it's important that they have distinct appearances for easy recognition.
- Dragon City: Eggs have the same theme as the dragons that hatch from them. For example, the origami dragon hatches from an egg made of folded paper.
- Dragon Vale has dragon eggs that are designed after their dragons. Common, two-element eggs usually have the color of one of the involved elements and a pattern based on the other, with the pattern part colored gold if it's a rarer variant; while rarer breeds have their own custom egg designs.
- Egg Cave: Eggs tend to be the same colour as the creatures that hatch from them.
- In The Legend of Spyro, purple dragons hatch from eggs of the same color. Because of their unique power, the birth of a purple egg is cause for much excitement and/or trepidation. This is a change from the source material, in which all dragon eggs were off-white and patterned with irregular pink-and-blue shapes (to emphasize the cuteness of the baby inside).
- MagiStream: Every magical creature resembles the egg it hatches from, an example being the purple koi fish, which hatches from a purple egg decorated with scales.
- Merge Dragons: Each dragon egg is patterned in such a way that you can tell what dragon is inside by just looking at them. Some are also textured such as the Grass Dragon Egg.
- Minecraft's Creative mode-exclusive spawn eggs are brightly colored and decorated with speckled spots, which share their colors with the creature within. For example, creepers' eggs are forest green with black spots, zombies' eggs are teal with moss-green spots, and spider eggs are slate-grey with maroon spots.
- Monster Hunter: Stories (and its sequel): Players collect new monsters by raiding nests for eggs to hatch, and the eggs are designed as a way for the player to identify the monster inside. Each monster grouping has a different pattern (for instance, Herbivore eggs are spotted with horizontal ovals, while aquatic Leviathans have a wave pattern), and the coloring usually matches the monster itself.
- Pokémon: Played with - in the main series, Pokémon eggs uniformly have a plain white design with green spots due to graphical limitations, similar to Yoshi eggs. The only exception is the event-only Manaphy egg from Generation IV, which has a unique sprite showing it to be translucent blue with a ring of yellow dots and a red center, similar to Manaphy itself, an aquatic Pokémon with a blue body, yellow dots for eyebrows, and a red gem over its heart. However, some spin-off games (as well as the anime) have unique egg designs for individual Pokémon.
- Hey You, Pikachu!: A Togepi egg, white with red and blue triangles, can be found and hatched while completing the Pokémon Picnic missions.
- Pokémon Channel: Various eggs appear on the Eggzamination: Hatch Up! channel. Based on their designs, the player can guess what Pokémon is in them and win money if they're right when the egg hatches. Some of the eggs are just plain white, though.
- Pokémon Puzzle Challenge: Four eggs are available as unlockables. Magby's egg has flames on the bottom, Elekid's egg is yellow with stripes, Igglybuff's egg is pink with swirls, and Cleffa's egg is pink with stars.
- Pokémon Snap: The three legendary birds' eggs appear and can be hatched by the player - a crystalline silver egg for Articuno, a yellow egg with lightning designs for Zapdos, and a white egg with a flame design for Moltres. (This was before the games introduced the breeding mechanic, as well as the idea that legendary Pokémon are unable to breed, with a few exceptions.)
- Sonic Adventure: The Chao are virtual creatures that can be raised in Chao Gardens and used to compete in races to win emblems. While the standard Chao eggs are white with light blue spots (as the standard Chao is light blue), other Chao eggs are the same color as the Chao inside them. Such examples include the Gold, Silver, and Black eggs that can be found hidden in the adventure fields, and the rare eggs that can be bought on the black market in the DX remake of the game and the Battle remake of Sonic Adventure 2.
- Stardew Valley: Regular chicken or bird eggs are usually inconspicuously brown, white, or a pale yellow as in real life, but the player can obtain special animals with appropriately specially marked eggs.
- Void chickens (red and black) lay black eggs with red spots.
- Dinosaur eggs are marked with green polka dots, matching the green Pepper Rexes they eventually hatch into.
- Golden chickens lay golden eggs.
- Super Mario Bros.: Green Yoshis will hatch from green-spotted eggs, blue Yoshis from blue-spotted eggs, etc.
- Temtem: Eggs can be obtained by breeding two compatible Temtem. The egg design is not specific to the individual Temtem, but is based on its elemental type (water eggs are blue with a wave design, fire eggs are pale orange with a flame design, etc.)