Complex sentence: Robert de Boron portrayed it as the vessel of the Last Supper; and "Peredur" had no Grail per se, presenting the hero instead with a platter containing his kinsman's bloody, severed head.
Split into simpler sentences: Robert de Boron portrayed it as the vessel of the Last Supper. The Welsh romance "Peredur" had no Grail per se, presenting the hero instead with a platter containing his kinsman's bloody, severed head.