|The following information is from the Adventure Time comic book series. It may not be part of the same canon or continuity as the animated series.|
Truth Field Projection Princess (short for "Mandatory Truthful Response Field Emitter And Polarity-Aligned Honesty Particle Atmosperic Wavefront Generator With Decoupled Quantum-Phased Linear Projection Matrix Princess") is a slang speaking princess with the power to emit energy fields that make people tell the truth. She helped Finn in his search for Ewblo by helping him interrogate wizards. Like most other princesses she has a crush on Finn.
She is green and has an orange dress and her crown is similar to Princess Beautiful's.
Comic Book Apperances
Issue #12 - She helped Finn to figure out who Ewlbo was by using her truth field. She then used it on Finn to get him to tell what was the best way he wanted to smooch a princess but he put his hand in his mouth so he could'nt talk.
Issue #15 - She was one of the princesses seen at the party.
She can use her mind to make a green field come out from her and everyone will tell the truth about what she asks them.