Indie-Pendence Trio is Undertale Trio Au that crossover between three Indie Games, Undertale, Bendy Series, and Spooky's Jump Scare Mansion.
The project has some addition to the character's abilities, storylines, and appearances that do not exist in the original game (Fanon) to make the story intensify and can be expanded.

Undertale by Toby Fox
Bendy Series by Joey Drew Studios
Spooky's Jump Scare Mansion by Lag Studios

Indie-Pendence Duo and Indie-Pendence Trio by EmptyAzurite

Undertale Alternate Universe
Murder Sans (Dusttale) by Ask-Dusttale

Horror Sans (Horrortale) by Sour-Apple-Studios

Killer Sans (Something New) by Rahafwabas

Insanity Sans (Undertale Insanity) by Zeero Danteero/UTC

Dusttrust Sans (Dustswap: Dusttrust) by Team Dusttrust/DillyWolf
[Dustbelief Papyrus (Dusttale: Dustbelief) by Aude-Jevel]

Scoundreal Sans by Draw Wolf

Fresh by Crayon Queen

Nightmare (DreamTale) by Joku

Error by Crayon Queen

Error404 (Alphatale) by SHADIKAL15