Not all characters were included. Those missing were:

• Arlan
• Argenti
• Bailu
• Bronya
• Gepard
• Hanya
• Luka
• Luocha
• Lynx
• Natasha
• Sushang
• Tingyun
• Topaz
• Yanqing
• Yukong

I got a bit lazy with gentags, please forgive me~

Also, the song is Interstellar Journey (星间旅行); which can be found here.

Why Caelus is a normal cake?

Theta0028 said:

Why Caelus is a normal cake?

The machine did and oopsie, as you can hear from the short 'beep'.
That aside, the green-shelled catcake is a special one that you can only get by digging in the hydroponics table.

Probably to avoid doing the Trash Cake twice, since Stelle got that.