Jap., fugen: All Good
In the oldest texts and among the Nyingmapa, the All-Father Samantabhadra is regarded as the Adibuddha and is usually shown in Yab-Yum with the All-Mother Samantabhadri or Kuntuzangmo (Tib., kun-tu-bzang-mo).
In the teachings of other Tibetan schools, Samantabhadra is one of the eight Bodhisattvas and the 'spiritual son' (emanation, manifestation) of Vajrasattva. As such, he is also known under the name of Ghantapani (Skt., Bell-Bearer).
Now to an Western mind, usually indoctrinated with Christian concept, the idea of an All-Father does sound familiar. This Tibetan version of it, however, does not at all fit. The All-Father Samantabhadra is not a deity at all! If one studies Nyingmapa scriptures, and especially Dzogchen, it becomes clear that Samantabhadra is a term to indicate the naturally perfect and unsullied state of mind ... the mind that creates all phenomena without being fooled into believing that these very same phenomena have any reality.
I'm saying this in simple and perhaps sloppy words, and I can only refer everyone interested to the works of great linguistic minds like Longchenpa.
See also Bardo Mandala