GS

GS (also known as Green Sphere) is one of the most important recurring characters in RPGs (well, BFDI ones). He is the (much) younger brother of Marble and would've been the heir to MarbleCo if it wasn't destroyed. He is first found in the Polluted Canyon as a gatekeeper. However, his hint stations are found earlier than that and are hosted by a MarbleCo robot.

History (Role in OG Taco Chronicles)
GS was a minor boss in the original RPG. He was the gatekeeper of the Polluted Canyon, and fought PP for permission to cross. His battle was Undertale-inspired, and after the fight, PP was given a choice to FIGHT or SPARE GS. He chose to SPARE GS, allowing GS to temporarily go with PP. The hint stations in this RPG were manned by Marble, but they were very scarce. If PP would've chosen to FIGHT GS, GS would've died. Marble wouldn't have appeared either. However, GS got much more important roles in later RPGs (notably Objects in Time and Object All Stars).

Backstory
GS helped his brother Marble out in MarbleCo's factory. However, some strange people appeared. Marble attempted to fight off the two, but he was unable to. Unknowingly to GS, Marble soon realized what the two were there for and helped them. However, a robot of Marble's activated a bomb, which would soon destroy MarbleCo and put Marble into a coma. GS was able to escape, but he swore to get revenge on the two that destroyed all he had. He fled to the nearby Polluted Canyon, which was where most of the wreckage and robot ended up in. He lived with the mutated objects (thanks to the acid from robots) and ended up becoming a great inventor himself. He began to place hint stations all over the world to help out the newly-formed object hero team. During the beginning of Taco Chronicles Plus, he is residing in the Polluted Canyon