This is a sub-page of Prerelease:Undertale.
SnowdinThis subpage covers concept art related to Snowdin and any characters first seen there.
WaterfallThis subpage covers concept art related to Waterfall and any characters first seen there.
HotlandThis subpage covers concept art related to Hotland (up to the MTT Resort) and any characters first seen there.
COREThis subpage covers concept art related to the CORE and any characters first seen there.
True LabThis subpage covers concept art related to the True Lab and any characters first seen there.
UI#
Various mockups of the battle system by Toby, including some simple placeholder designs, and the creepy Toriel from earlier. Most notably, there were more options for the main choices, such as Check, Talk (which would generally be merged into ACT), Magic (which was completely scrapped), Goods (which became ITEMS), and Run (which would be combined with Spare and turned into the MERCY option).
Various tries at figuring out the final design of the battle interface, most notably showing off the unused Energy magic mechanic. Along with this, there are early versions of the final's main choices, with the Spell icon actually going unused in the final game's files. The flavor text in the second image, another reference to Gunstar Heroes, would later be reused as flavor text while fighting Froggit.
Various mockups of the overworld menus, including an early spelling of Undyne's name, wowee! Most notably, SAVEing was originally a menu option that could be chosen anywhere, and it would track how many kills the player has, rather than the stats screen showing it after killing 21 monsters.
- The cell phone was going to be Frisk's friend, but this idea was scrapped for being "really bad".
- The Sol Armor and Planet Buster are both references to Brandish, and were also equippable items in the EarthBound Halloween Hack that Toby Fox made years prior. The sword drawing resembles the eponymous sword in Brandish 2: The Planet Buster.
The early save menu seems to be used in the GAMETEST_7 build.
Loading screen design by Temmie that Toby removed because he preferred the loading screen to look shitty.
Mockup of the demo's instruction manual; surprisingly, drawn by Temmie on a trackpad.
Mockup of the dating sim sprites during Papyrus' date, with Aaron's sprite used as a placeholder.
Every major boss fight was supposed to have a different unique background, such as this floating one for Asgore (which actually was programmed). In the end, all but Undyne's were scrapped.
All of these sprites were meant for the very end of Papyrus' "really cool regular attack", which originally would've had bone attacks and then devolve into tons of ridiculous things. Ideas include an entire circus and a row of 19 buses (which is a reference to the Homestar Runner short, Strong Bad Email #87 - Mile). This was scrapped for "every reason", according to Toby. A remnant of this still exists in the final attack, with the sprites for the long row of bones being called spr_coolbus.
A placeholder for the console versions' borders, with various humorous images on the sides. Hey, that Papyrus one looks familiar...
Cutscenes#
Intro#
Temmie's very first sketches of the game's intro. In the PDF version of the art book, Toby explains that the intro was originally going to have Frisk fall down into the Underground instead of Chara, but Temmie accidentally drew one stripe on their shirt instead of two. Instead of changing this, Toby decided to work it into the story, and have the intro tie into the cutscene during Asriel's boss fight.

Slightly more finished versions of the intro by Temmie. These were actually used as placeholders in the GAMETEST_7 demo mentioned above.
Scrapped Flowey Cutscene#
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To do:
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-> if you defeat asgore in one hit
uhhhhh
you win?
(burrows into the ground)
credits play with goofy sitcom theme
song music
Storyboard for a never-implemented cutscene that would've occurred if the player somehow managed to defeat Asgore in a single hit. In the final game, the only time this happens is during the Genocide Route, where the outcome is far more serious. Unused Flowey faces meant for the scrapped cutscene are also still left in the final game.
(Source: @tobyfox)
Pre-Asriel Fight#

The cutscene before the Asriel fight was so complicated that Toby decided to make a rough storyboard of it. The end results are... interesting, to say the least. Of note is that Papyrus' "pepis" text, a reference to a fake swear word used as an in-joke among Toby's circle of friends, bears an uncanny similarity to the "pipis" sign that accompanies the enemy/attack of the same name in Deltarune.
Asriel's Flashback#
Temmie's original storyboard for the Asriel flashbacks. Toby came up with different ideas later on, shown below.



Storyboards for Asriel's flashbacks to his life with Chara near the end of his battle in the True Pacifist route, plus some concept portraits of Asriel himself. According to Toby, several planned scenes had to be cut from this sequence in the final game for timing purposes; indeed, of the scenes shown here, the only ones present in-game are Asriel encountering Chara after they fall into the Underground and Asriel & Chara holding bouquets of flowers. Toby's notes, from left to right and top to bottom, read as follows:
eat pie
read books
play in the flowers
they're all wrapped up in bandages, like mummies.
3 poses:
- asriel holding flowers, chara holding too many
- them eating pie, chara holding a knife → knife next to chara
- them looking at stars, parallel to earlier
The contents of these notes also confirm that "Chara" is indeed the canon name for the Fallen Human that the player names at the beginning of the game.
(Source: @tobyfox)
Other#
Concepts for the logo of the game. The artist is not listed in the art book.
Drawing made by Temmie right after the demo released for the Kickstarter, showcasing a few early, silhouetted versions of characters that would appear later.