Constellation cards are secret keys to hidden realms and areas.

There are 12 Constellation Cards, and all of them are found and stored independent of save files. Each has a special function, and collecting all 12 has its own function.

Name Appearance Unlock Collection Image
Aries A photo of a young goat in a field of golden flowers Enables
Save Everyone Ending
Given upon completion of the True Pacifist Route
Card aries
Taurus Delta Rune with a red background Grants access to New Home's 'room under renovations' Hidden underneath a large power crystal (1/2)
Card taurus
Gemini A photo of a kid in a striped shirt Grants access to the Gemini room in the Dev Apartments Found in the patch of golden flowers in the Caverns after True Pacifist
Card gemini
Cancer Has 'Don't make fun of me' scratched on the back Grants access to Sans' basement Hidden underneath a large power crystal (2/2)
Card cancer
Leo It's swipehole looks like a swirling vortex of fire Grants access to Zone Zero (required for True Pacifist) Alphys gives this to you during her date (if you don't have it)
Card leo
Virgo Delta Rune with a blue background Grants access to the Caverns' 'room under renovations' Hidden in Toriel's room
Card virgo-0
Libra There is a signature on the front face of the card, it's extremely rigid. Grants access to Arial's room Hidden in Zone Zero
Card libra
Scorpio This card's swipehole ends in the shape of a bent hook, with a star in its grasp Enables
the first part of the Bedtime Story
Hidden underneath the sheets covering Toriel's throne
Card scorpio
Sagittarius Advertisement for MTT XXL Pro-Blasters Grants access to So Sorry's art class at MTT Resort Purchase at MTT Resort
Card sagittarius
Capricorn This card's swipehole vaguely represents the word 'AURORA’ Grants access to Room 274, accessible within Aurorafall On display near the counter of the Dev Apartments
Card capricorn
Aquarius Has a crude drawing of an onion monster on the back. Has no function Draw up the fishing pole in Starrin' a third time.
Card aquarius
Pisces A "Happy Birthday" clip art has been printed on it. Grants access to the Dev Apartments In
Sans's basement
Card pisces
All collected Enables
the second part of the Bedtime Story