The Carbon Dog is the first form of the eighth and final Sanctuary Guardian of EarthBound. It is weak to PSI Freeze and PSI Flash. After 1672 or more damage has been dealt to Carbon Dog, it emits a rainbow of colors and transforms into Diamond Dog.
- The transformation from Carbon Dog to Diamond Dog refers to the process of carbon becoming diamond through exposure to extreme heat and pressure.
- Carbon Dog is the only Sanctuary Guardian with two forms.
- Carbon Dog's overworld sprite shines slightly brighter than those of the other Sanctuary Guardians.