Introduction (also known as Survey) is the beginning part of Deltarune. Various questions are asked with the purpose of creating a vessel for Deltarune's world and identifying its creator.
The introduction plays once until the game is saved for the first time. It can only be replayed on a new save file.
The customization starts with the building of a body (also called a "vessel"). The first choice is the HEAD which has 8 options, the BODY with 6 options and the LEGS with 5 options.
These questions are meant to give the vessel a personality:
- What is its favorite food?
- Your favorite blood type?
- What color does it like most?
- Please give it a gift.
- How do you feel about your creation? (It will not hear.)
At the end of the questionnaire, the player is asked if they answered honestly, then asked if they have acknowledged the possibility of pain and seizure. The player names the vessel and then enters their own name.
Setting certain names for the vessel or creator alters the voice's response.
- By default, the voice says WE CALLED IT "<Name>." when naming the vessel and "<Name>". EXCELLENT. TRULY EXCELLENT. when naming the creator.
- If the vessel's name is set to "GASTER," the game returns to the beginning of the intro upon typing the last letter. If the creator's name is set to "GASTER", the game shuts down upon typing the last letter.
- If the name is set to either "QC," "SANS," "UNDYNE," "TORIEL," "ASRIEL," "ASGORE," "PAPYRUS," "JOCKINGTON," "GERSON," "BRATTY," "ALPHYS," "BERDLY," "CATTI," "CATTY" or "RUDY," the voice says "<Name>." AN INTERESTING COINCIDENCE. when naming the vessel and "<Name>." HOW INTERESTING. when naming the creator.
- If the name is set to "SUSIE," "KRIS" or "NOELLE," the voice says "<Name>." AN INTERESTING COINCIDENCE. when naming the vessel and "<Name>." YOU ARE ABOUT TO MEET SOMEONE VERY, VERY WONDERFUL. when naming the creator.
- If the creator is named the same as the vessel, the voice says OF COURSE OF COURSE. OF COURSE THEY ARE THE SAME.
After this, the vessel is discarded and the game states "No one can choose who they are in this world". The game then finally starts with the player controlling a character called Kris.
- Interestingly, the only names that cause the "Interesting coincidence" response are the characters met in Hometown. Characters who only appear in Undertale, but do not appear and/or are mentioned in Deltarune (such as Grillby or Mettaton) don't have a special response (except Papyrus, although he is alluded to), nor do the characters who only appear in the Dark World (such as Lancer or Ralsei).
- After the vessel is discarded, every save file appears with the creator's name on the save.
- The character limit when naming the vessel is 9 (eg. DELTARUNE) whereas the character limit when naming the creator is 12 (eg. WINDINGASTER).
- The introduction music resembles the track "Giygas' Intimidation" from Earthbound.